| 00:04 | Hello? OK. So, um is kind of divided into two |
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| 00:18 | right? So, what we're gonna is we're going to finish out the |
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| 00:21 | and really what we're gonna be doing this point is we're moving away from |
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| 00:24 | cell and we're moving out to the itself, like the, the, |
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| 00:29 | named muscle. And we're asking the , you know, like, how |
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| 00:33 | it work in a very generic All right. So there's going to |
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| 00:36 | a lot of vocabulary that kind of along with it. And then once |
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| 00:39 | finished with the muscle, what we're to do is we switch and we're |
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| 00:42 | to shift gears into the nervous system that shift represents the point where everything |
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| 00:48 | from beyond that point is nervous system the end of the semester. So |
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| 00:53 | a lot of nervous system and the is, is that why we spend |
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| 00:57 | much time on it? I don't , it's, it's just is, |
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| 01:02 | not like there's really that much, six lectures in a regular semester. |
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| 01:07 | it's crazy. So here we we're going to start here with origins |
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| 01:11 | insertions, origins and assertions are simply points of attachment for a muscle against |
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| 01:16 | bone. And there's some generic terminology generic ways that you can remember |
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| 01:21 | All right, an origin simply is point where the muscle attaches at the |
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| 01:27 | end. So the one nearest the and the insertion is generally speaking, |
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| 01:31 | one that's the distal attachment. So , what we're doing in the way |
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| 01:36 | our bodies are built is that with origin, this is going to be |
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| 01:40 | stationary attachment. So we're moving the towards the body. All right. |
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| 01:45 | then the assertion is part where you the mobility. So very, very |
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| 01:51 | origin stationary. And when you're dealing the insertion, that's what you're |
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| 01:57 | Now, when we say this, also the type of attachment is slightly |
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| 02:02 | . Now, we talked about there tendons and very often there might be |
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| 02:05 | on both sides. But typically, we say is that we have a |
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| 02:09 | attachment when it comes to the Whereas we have a tendinous attachment or |
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| 02:14 | fibrous attachment when we're dealing with the . And so what you're doing is |
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| 02:19 | that muscle contracts, what what you're is you're pulling on that tendon and |
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| 02:24 | tendon stretches just before it begins pulling the bone. All right. So |
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| 02:30 | kind of an easy way to think this. What I'm doing is I'm |
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| 02:33 | force and I'm moving towards the origin it's the insertion that I'm pulling and |
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| 02:40 | . So you're focusing the force there move it. Now, when we |
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| 02:45 | about the muscles, we're keeping it simple. All right, because movement |
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| 02:50 | not just simply a single muscle. right. When you go and |
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| 02:56 | you typically are using multiple muscles in exercise. Very rarely. Are you |
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| 03:02 | ? Like, I'm just working one . All right. I mean, |
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| 03:06 | going to use something really simple, a bench press right when you go |
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| 03:10 | or just a simple curl, it's , oh, well, I'm doing |
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| 03:13 | single movement. Er, go, doing one movement, er, go |
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| 03:17 | muscle and it's actually, there's three in the biceps, there's, |
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| 03:21 | or there's one muscle on the three on the back side. And |
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| 03:24 | every time you move you're actually using of those muscles together. Plus on |
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| 03:29 | of that, you have muscles in back that are stabilizing you. And |
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| 03:33 | this terminology, um, that we're to see here and I thought I'd |
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| 03:37 | the button over but apparently I didn't gonna keep going forward. Um, |
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| 03:42 | any type of movement you do is bringing in multiple muscles to make that |
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| 03:48 | happen. All right. So there's terms that you should be familiar with |
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| 03:52 | four because one that has not highlighted here, the agonist, the agonist |
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| 03:57 | the muscle that you're focusing on. is the one that's doing the |
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| 04:00 | uh, movement. All right. the a, so like if I'm |
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| 04:04 | something like this, the agonist is the lifting portion, right. The |
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| 04:10 | is the muscle on the opposite basically doing the opposite. It's, |
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| 04:15 | , it's relaxing while this muscle is . So for every muscle you have |
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| 04:20 | , you have muscles relaxing because the that we don't think about is when |
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| 04:24 | doing that curl, even though I'm up, I'm gonna put that bar |
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| 04:27 | down again, right? And then bar goes down. I have another |
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| 04:32 | that's contracting and a muscle that's So the agony is the muscle that |
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| 04:36 | the agnus is the muscle relax in movement and they are in opposition to |
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| 04:41 | another. All right. And so I'm put, putting the muscle |
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| 04:46 | my bicep, in this case would the agonist, but tricep in this |
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| 04:50 | would be the antagonist. But when curling back down the muscle that's in |
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| 04:56 | is my tricep, right? It's the agonist, the antagonist would be |
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| 05:03 | bicep as I'm putting the muscle back . All right. So what we're |
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| 05:07 | is we're stabilizing the movement. If muscles contract at the same time, |
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| 05:13 | basically pulling ropes in the same direction the arm wouldn't move, right? |
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| 05:19 | they, they are opposite each So one has to contract and one |
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| 05:23 | to relax. So it's really remember is one that's doing the movement. |
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| 05:26 | antagonist is opposing the movement. All . Yeah. To, uh, |
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| 05:32 | , no, no. So we've moved upwards so the tit would |
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| 05:35 | inside the individual cell, right? , when you're thinking about the cell |
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| 05:38 | all those mild fibri, the titan the spring portion that allows the muscle |
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| 05:44 | be first, be contracted and then return back to its original shape. |
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| 05:48 | , that's a good way to think it. The relaxation couldn't occur unless |
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| 05:53 | titan was there. Right. But , the relaxation is the, is |
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| 05:58 | movement of the muscle as it's stretching out to its original shape. |
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| 06:04 | the synergist is the muscle that that's not part of the actual movement |
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| 06:10 | if I go in. All So I worked out yesterday and this |
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| 06:13 | the first time we've done shrugs in long time. You know, what |
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| 06:16 | are, you pick up the people out? No, you basically pick |
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| 06:20 | whites and you do this because you're shrugging. Right. You know, |
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| 06:24 | so we do heavy weights for you know, I mean, it's |
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| 06:27 | , I haven't done it in a and it was like, ok, |
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| 06:29 | up the £70 weights and I pick up on both hands and I start |
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| 06:33 | the shrugs. If I picked up £70 weight and I didn't have a |
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| 06:36 | , what would happen. So I'd over. Right. So the muscles |
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| 06:40 | my back are serving as a While I'm lifting up the weight. |
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| 06:47 | . So the synergist stabilizes the body you're in movement, it's not part |
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| 06:52 | the actual act, it's outside of act, helping you to stabilize your |
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| 06:58 | while the movement is taking place, agonist working against the antagonist is called |
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| 07:05 | inhibition, right? And really what is is so we're gonna learn a |
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| 07:09 | bit later when we go further into nervous system, we're gonna talk about |
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| 07:13 | how we regulate or how we stimulate muscle contraction. All right, |
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| 07:19 | we have these motor neurons and so neurons are always excitatory when they're innervating |
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| 07:25 | muscle. All right. But what want to do is you want to |
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| 07:29 | or prevent the antagonist from contracting while contracting the, the agonist. |
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| 07:35 | the reciprocal in inhibition is, is I am stimulating an agonist, I'm |
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| 07:42 | the of the antagonist and vice Well, I mean, once they |
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| 07:47 | , they, you refer to them agonist and antagonist. All right. |
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| 07:51 | basically, it's the control that basically , hey, while this is |
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| 07:57 | I want that to relax because if both contract at the same time, |
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| 08:01 | gonna get no movement. All I was thank you the lower back |
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| 08:10 | . But, but yes, I , your legs could be a |
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| 08:14 | So like when you're doing a dead , right, you're, you're primarily |
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| 08:17 | it in the lower back. Those the muscles you're using but what's stabilizing |
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| 08:21 | is your thighs and your calves and really upper body as well, |
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| 08:26 | ? So a lot of muscles are . So, so very often what |
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| 08:29 | see when, you know, if you go and look at |
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| 08:33 | uh, an exercise plan, the plans, like swings and stuff like |
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| 08:38 | , they're not there to focus on single muscle right. There are exercise |
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| 08:42 | can do to focus on a single or muscle group, you know, |
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| 08:46 | that you can get that buff look you can walk around looking cool or |
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| 08:49 | or whatever. But really, if want to exercise, you do, |
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| 08:53 | do, uh, or you want do development, what you're gonna do |
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| 08:56 | you're gonna do muscle groups like a where it's like I'm lifting up. |
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| 08:59 | so I'm changing the direction of uh, of the movements of my |
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| 09:03 | is actually switching which muscle groups I'm using. So that's probably what your |
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| 09:09 | are doing or when they're going off exercising, you're like, what does |
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| 09:12 | have to do with swimming? it has to do with muscles that |
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| 09:15 | don't know that you actually use and to strengthen as an example. He |
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| 09:22 | , you do absolutely unless you're sitting a machine and that's, that's the |
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| 09:28 | of the machines, right? Free are much better because you're using more |
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| 09:32 | your body to do the exercise. a machine gets you to focus specifically |
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| 09:37 | that muscle. Now, I have , a horrible rotator cuff like this |
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| 09:41 | probably should be worked on, you . So there are days when, |
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| 09:46 | I can't actually work free weights. so I'm like, with my, |
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| 09:48 | guy that I work out with, like, we gotta go do machines |
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| 09:51 | I, I don't have to put much focus on that shoulder. I |
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| 09:56 | it when it makes me do kills me. Dip suck. Just |
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| 10:01 | you know. All right. So are two different primary types of |
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| 10:08 | All right, we have isotonic and contractions. When you think of a |
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| 10:13 | , you're thinking primarily of an isotonic , right? Isotonic simply says I'm |
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| 10:18 | to generate some sort of muscle which means I'm going to generate some |
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| 10:22 | of force and that is going to once I generate that force, it's |
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| 10:27 | to remain constant and I'm going to the length of my muscle size. |
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| 10:31 | like, OK, well, what does that mean? All |
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| 10:33 | So we all agreed that was about leader. So one leader is about |
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| 10:40 | . How much do you remember? leader equals 1 kg? That's |
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| 10:45 | Thank you. That's the whole beauty the metric system, right? 1 |
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| 10:51 | , which 1 g equals 1 yada yada. All right. So |
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| 10:56 | got a kilogram of weight here. right. In order for me to |
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| 11:00 | that up, I have to generate tension in the muscle to overcome the |
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| 11:05 | kg of weight. All right. what I do is I go in |
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| 11:08 | and I start recruiting motor units, motor unit doesn't do the movement, |
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| 11:12 | motor units, not 345. And I get to the point where I've |
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| 11:16 | enough motor units so I can now up and curl this. So what |
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| 11:20 | done is I generated the right amount tension to overcome this. I didn't |
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| 11:25 | too much tension in it because what if I put too much tension in |
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| 11:28 | muscle, what do you think is happen? I'm gonna throw it over |
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| 11:31 | shoulder. Exactly. So, the here is that in a concentric uh |
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| 11:36 | , I'm gonna produce enough force to the, the amount of work needed |
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| 11:41 | move the load. That's the Ok. Now, what, what |
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| 11:48 | the, the changing the length of muscle? All right. Well, |
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| 11:52 | I started my muscle had a specific , I don't know if you guys |
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| 11:55 | all see right. When I started , what happened to my muscle |
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| 12:02 | See, look at that, what they doing? It's shortening, |
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| 12:06 | And then when I put it what happens to the muscle, it |
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| 12:12 | . All right. So there's a and there's a length and lengthening |
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| 12:15 | And so we have a name for that when you shorten the muscle, |
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| 12:19 | called a concentric contraction and when the is lengthening, it's an e centric |
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| 12:26 | . All right. But notice I'm just enough tension to overcome the |
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| 12:32 | All right, then we have the one. The isometric contraction, the |
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| 12:37 | contraction is I'm not going to change muscle length at all. In |
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| 12:41 | what I'm gonna do is I'm gonna tension in the muscle. I'm gonna |
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| 12:44 | developing tension in the muscle and it's keep growing and growing and growing. |
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| 12:47 | I'm never going to produce enough tension overcome the load. Now, you |
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| 12:51 | think about this as you go get a weight, you know, |
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| 12:54 | you know, on, on a and it's like, I'm just going |
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| 12:56 | stack it up to like £500 and gonna just try to push it |
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| 12:59 | You're never gonna move the thing, ? But for you to visualize |
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| 13:05 | would you all agree that this wall a force that, that I can't |
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| 13:10 | ? Right? So I can push against it, right? So there's |
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| 13:13 | little bit of force, but the doesn't move. Does my muscle length |
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| 13:18 | here? I'll just do this. you can see the beautiful gun, |
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| 13:22 | ? I can push and I can and I can push and I can |
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| 13:24 | and I can push and the muscle change length, but I'm increasing the |
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| 13:28 | of tension to try to overcome the . So an isometric contraction is when |
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| 13:33 | build up more and more tension, you don't change the muscle length. |
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| 13:37 | , this used to be a really type of exercise back in the |
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| 13:42 | Right. Moms would be at I mean, because it really was |
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| 13:47 | . It was like they stay at mom and they would do their exercises |
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| 13:51 | the morning, they turn on the station because not everyone had cable and |
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| 13:55 | had like, the morning exercises and would sit there, ok. Put |
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| 13:59 | arms together. Now, push. right. And what you're doing is |
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| 14:05 | creating tension and you're actually causing the to contract, but you're not creating |
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| 14:09 | sort of movement. That's an right? It's just like lifting up |
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| 14:14 | weight. The difference is when you up a weight, it feels like |
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| 14:16 | doing something when you're doing this, doesn't feel like you're doing anything other |
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| 14:19 | creating force, but it's still a to build up tension and do |
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| 14:25 | Now, this is just a visual of it. You can actually do |
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| 14:28 | in a laboratory. You can get weight, you can attach a muscle |
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| 14:31 | it, kind of like an And then what you do is you |
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| 14:34 | electrical activity to it. And what see is if the muscle has, |
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| 14:39 | able to produce tension, it will the weight. But if you create |
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| 14:42 | weight that's too big, the muscle be able to create the tension but |
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| 14:46 | won't be able to contract like you in the concentric. So this is |
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| 14:49 | just a visual representation of that. right. And over in the little |
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| 14:54 | , it shows you where the tension being developed and the kind of the |
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| 14:57 | the rest or the length that's staying whereas the length is changing over |
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| 15:03 | So does that all make sense? versus eccentric isotonic versus isometric? It |
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| 15:09 | says in the name Iso iso, metric is length. Tonic has to |
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| 15:17 | with the tension. OK. The tension versus same length. Now, |
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| 15:25 | muscles have these four plus one Every textbook used to say four and |
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| 15:30 | this one decided to throw in another . So, all right, first |
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| 15:34 | , all muscles are contractile, that they can forcibly shorten when stimulated. |
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| 15:39 | right. So the muscle changes Now, I have shortened here. |
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| 15:43 | probably it can lengthen as well. right. The reason we just leave |
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| 15:48 | short in there because we're going to about returning back to its original |
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| 15:51 | All right, they're all excitable, that they respond to some sort of |
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| 15:55 | stimulus to cause them to change their . Right? In other words, |
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| 15:59 | can give them Ac Cole and they're to contract. All right, they're |
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| 16:06 | , meaning that you can stretch a beyond its resting length. All |
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| 16:12 | Now, when you stretch, that's you're doing. Your muscles are in |
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| 16:15 | natural state. And then you can , OK, I'm gonna stretch out |
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| 16:18 | it's like, oh yeah, I feel it all right back in there |
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| 16:21 | I'm just stretch, stretching out my . In that particular case, I'm |
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| 16:25 | beyond the resting length. All They also have the ability to |
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| 16:31 | So they are elastic. All So when I contract it, they're |
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| 16:35 | stuck in that position, they can back to their original position. All |
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| 16:40 | , that's, that's one of the characteristics. And finally, and why |
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| 16:46 | including this now and why they didn't the other textbooks. I don't know |
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| 16:49 | that they're plastic. All right. , when you hear the word |
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| 16:52 | don't think Barbie think something that is . All right. So muscles can |
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| 17:00 | based on their usage. Now, I say adapt here, that doesn't |
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| 17:03 | they're gonna change their nature. All . A plastic thing basically changes in |
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| 17:10 | way. In the case of I can make muscles stronger or I |
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| 17:14 | make muscles weaker. Right? So the plasticity here. They're going to |
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| 17:22 | stronger based on usage and they're gonna weaker based on lack of usage. |
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| 17:27 | that's the idea. That's the key . All right. Now, here's |
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| 17:32 | first weird concept. All right. , this is more of a kinesiology |
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| 17:38 | thing. So, if do you any kine majors? No. |
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| 17:42 | So what, this is a strength cycle is what you use to help |
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| 17:50 | the, um, the force that gonna produce. And basically what it's |
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| 17:54 | use, it's going to take advantage both that e and concentric contraction. |
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| 18:00 | what you're gonna do is you're gonna so that you have kind of like |
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| 18:04 | spring like um energy. So as I'm stretching it, I'm storing |
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| 18:09 | energy. And then what I'm gonna is I'm going to quickly switch over |
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| 18:13 | a contraction so that the energy is that stretch to create more force in |
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| 18:19 | contraction. All right. So in , in the shortening phase. All |
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| 18:25 | . So the example here is a . That is what they're trying to |
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| 18:29 | here. And it, I it's a static picture. All |
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| 18:32 | But think about when you're trying to something high, do you put your |
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| 18:36 | flat and then jump or would you on your tip toes and then you |
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| 18:40 | down and then you jump up, ? What you've done is you've, |
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| 18:45 | you go up on your tip toes you've now stretched that muscle, you've |
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| 18:49 | into the eccentric phase and then when push down, you're doing a quick |
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| 18:53 | so that you can then spring up , right? So the idea here |
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| 18:58 | I'm creating more force so I can greater height. Did you guys ever |
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| 19:03 | ever have to do that? the, the thing where they put |
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| 19:07 | little things to see how high you jump. Did you ever do that |
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| 19:10 | high school? Yeah. Basketball. know they make us do that. |
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| 19:15 | . They kind of did as That was a long time ago. |
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| 19:21 | , sticky nuts now. Yeah. , what they used to have is |
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| 19:24 | have these flags that were sticking out , I mean, and I say |
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| 19:28 | , they're plastic that are on, a hinge. And so what you'd |
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| 19:31 | is you'd see how, and you'd up there and you'd whack and as |
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| 19:33 | flags as you could knock over was height and they knew what the height |
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| 19:37 | for each of those. Yeah. anyway, so that's the strength shortening |
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| 19:46 | . Just this, this ability to greater force using eccentric and concentric. |
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| 19:52 | amortization phase is simply the switch between two. And so you can visualize |
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| 19:57 | and you can just practice it We just try to jump with a |
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| 19:59 | foot. I don't think you It's weird. I mean, |
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| 20:03 | you know, I mean, how inches am I getting here if I |
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| 20:09 | ? You know, and then see difference. Glad I still have a |
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| 20:16 | bit of athletic a bit, just little bit. The older you |
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| 20:19 | the harder it is. All The second thing that's kind of |
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| 20:26 | what new muscles have is a relationship the amount of force and velocity. |
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| 20:31 | , concentric and centric contractions have a type of relationship. So, when |
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| 20:37 | dealing with concentric reactions, reactions, , the force is going to be |
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| 20:43 | related to velocity. In other the greater the force, the slower |
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| 20:49 | muscle moves. All right, the force, the faster the muscle |
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| 20:55 | All right. Now, the easy to visualize this is again, think |
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| 21:00 | lifting something up and curling it towards body. All right, if you |
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| 21:04 | something light, you can move it . If you have something heavy, |
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| 21:10 | force, less velocity, right? would be an easy way with regard |
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| 21:15 | the E centric, you have And again, I'm using the |
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| 21:20 | Remember you have E center and concentric or contractions all over the place, |
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| 21:24 | it's an easy visualization. So if doing an E centric contraction force and |
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| 21:29 | are directly related. All right. the more force I have, the |
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| 21:34 | the contraction is taking place. All . And remember what you're doing is |
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| 21:38 | allowing the muscle to relax or expand longer. And so you can sit |
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| 21:44 | if I have this massive weight, going to happen is I want not |
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| 21:49 | to have great force to resist the as it tries to fall back |
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| 21:53 | That contraction has to be fast enough keep it from going, right? |
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| 21:58 | basically restricting the movement. All So the relationship I need you to |
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| 22:05 | here is this force with regard to is going to be uh inverse to |
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| 22:12 | so the bigger the force, the lower the velocity and vice versa, |
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| 22:18 | it comes to eccentric, the bigger force, the faster the velocity, |
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| 22:22 | greater, the quicker the contraction takes , right? It's not the speed |
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| 22:27 | which you can move. It's how can the thing contract. All |
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| 22:34 | And so that just kind of allows to kind of visualize what that |
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| 22:41 | So to turn it into anatomy because all this stuff really was just |
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| 22:45 | of physiology. How do, how muscles behave? Right? Concentric versus |
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| 22:50 | centric agonist versus antagonist. Um all this is kind of a |
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| 22:56 | What I wanna do here is I want to allow you to kind of |
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| 23:00 | how these muscles might be arranged. so your muscles have these different shapes |
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| 23:08 | to the tendons that are attached to . All right. And so we |
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| 23:12 | what are called pinnate muscles and we what are called non pinnate. |
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| 23:16 | again, this is language, but can make it simple pinnate refers to |
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| 23:21 | a feathering. All right. So other words, it's the direction of |
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| 23:25 | fiber relative to the tendon. If have a tendon that's going up and |
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| 23:31 | , if the muscle fiber is running the same direction as the tendon, |
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| 23:35 | we refer to it as being non . But if I have a |
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| 23:39 | a tendon and I have the fibers the muscle going at some odd angle |
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| 23:44 | that, that's referred to as like a flag, right? That's |
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| 23:49 | pinnate, that's where it comes But I think of it as |
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| 23:52 | right? I mean, does that of look like a feather to |
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| 23:55 | Kind of that kind of look like feather to you? You can say |
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| 23:59 | of, it's not, it's gonna perfect. All right, when you're |
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| 24:03 | with a pinnate muscle, it's like being on the or sorry, non |
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| 24:07 | muscle, it's like you being on end of the rope, all the |
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| 24:10 | that's being applied uh is direct in same direction as that tendon, |
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| 24:16 | So it's a parallel line. So can produce higher velocities and you have |
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| 24:21 | Sarcos. So you're able to produce force directly down that line here, |
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| 24:28 | gonna put force, um you're gonna a greater force because you're actually not |
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| 24:33 | directly along the line. You're pulling an a bleak angle to that |
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| 24:38 | And so when that muscle contracts, you're doing is I have to have |
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| 24:42 | and more fibers to get it to . So you put this massive amount |
|
| 24:47 | force behind it just to get it move a little bit. All |
|
| 24:52 | So we'll see different sorts of movements you have pinnate versus non pinnate. |
|
| 24:59 | again, notice I'm not asking to the muscles or even the different |
|
| 25:03 | So here's unipennate, you can see , it's on one side here, |
|
| 25:07 | created a great amount of force, I'm pulling on both sides. That's |
|
| 25:11 | getting two people on a rope and in the same direction at the same |
|
| 25:15 | , that'd be Bipin eight using multi . And here you can see, |
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| 25:18 | in a direct line. I'm in direct line. Yes, ma'am. |
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| 25:26 | force is the amount of tension you . So think of its strength. |
|
| 25:30 | right. This, the velocity simply how quickly the muscle responds, how |
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| 25:35 | it produces its force. All So you don't have to necessarily produce |
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| 25:41 | lot of force to be fast. mean, and again, it's how |
|
| 25:46 | the contraction takes place, right? you can think of the contraction, |
|
| 25:49 | measure when you see a picture of . If you put it on a |
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| 25:52 | like this, we say we have contraction goes up and goes down. |
|
| 25:56 | a greater velocity would be like right? So it goes up |
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| 26:03 | comes down quicker. All right. this would be uh the, the |
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| 26:07 | of tension in this direction. Um is this way that would be |
|
| 26:13 | That's tension and philosophy. All I want to make your lives easier |
|
| 26:26 | . OK. How are muscles All right. I said this |
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| 26:30 | I'm gonna say it again. I'm say it again probably another three times |
|
| 26:33 | the semester. I don't know. just comes up. Biologists are simple |
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| 26:37 | anonymous are simple people. We name for what they look like or for |
|
| 26:39 | they do right the end. So you look at a name and you |
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| 26:43 | confused and you're like, I don't , stop, remember my little sage |
|
| 26:48 | here, you're smart enough to figure names. All right. Even if |
|
| 26:53 | a $10 word and we're gonna see $10 words today. All right. |
|
| 26:57 | we're gonna see a lot more in couple of days. All right. |
|
| 27:00 | we gotta do is take that step and say, I'm not going to |
|
| 27:02 | frightened by the words because we use to describe location, position, |
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| 27:09 | size, shape, origin, all of stuff like that. I'm just |
|
| 27:12 | show you some examples. What do think erectus means? What, what |
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| 27:16 | does erectus look like? Go? . Well, let's try another |
|
| 27:23 | Huh? No, no. Let's it simple. Keep it simple. |
|
| 27:27 | think scientifically. Don't think of body , think of position or structure. |
|
| 27:35 | ? Straight. Uh How about, the word that you'd use to |
|
| 27:38 | Straight? Standing up, correct. said erected in glass. Yeah, |
|
| 27:47 | correct. Correct. Now, you , you're Latin. Ok. |
|
| 27:54 | What does that word look like? . Short. Why? What's a |
|
| 28:09 | that you'd say? That's, that sounds like, huh? |
|
| 28:14 | you see. Don't make it You're making, you're trying to make |
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| 28:17 | hard. Ok. Here's really Latin. Yeah, that's, you |
|
| 28:22 | , difficult right. Longest would be , right? OK. Notice what |
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| 28:26 | doing on our side. Major minor . Very vast. Yeah. So |
|
| 28:36 | see what we're getting at here obviously, the names themselves are gonna |
|
| 28:40 | specific, right? We have things are shapes. What do you think |
|
| 28:48 | deltoid is shaped like? Thank Triangle. What do you think the |
|
| 28:54 | is shaped like the rhombus? OK. How about the quadratus |
|
| 29:02 | All right. So we're dealing with again. Can you imagine sitting |
|
| 29:06 | You're, you're cutting up a cadaver you're like pulling out these big giant |
|
| 29:10 | and you're like, well, what I gonna call this? Well, |
|
| 29:12 | kind of shaped like a square. it's the square muscle actions, |
|
| 29:22 | What is it gonna do? Lifts ? What's the abductor do? Puts |
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| 29:25 | down? What does the depressor Puts it down? Extensor. |
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| 29:32 | flexor flexes. Oh, here's a one. The elevates, right? |
|
| 29:41 | , it's there and the opponents right . Do you see we have a |
|
| 29:56 | called the lavater? Scali. What you think? It does? I |
|
| 30:01 | no idea. All right, it the scapula. All right. So |
|
| 30:08 | often that's the names of the muscles you specifically something about them. |
|
| 30:14 | if you ever get lost because I don't know how they do the |
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| 30:18 | over there. If you have to like the, the positions, do |
|
| 30:22 | do the lab positions? So this how they used to do, |
|
| 30:25 | anatomy labs is it have 24 50 stations and you'd go in there with |
|
| 30:30 | piece of paper and you'd have to to the station and you had 30 |
|
| 30:34 | to answer the question and then you to the next 1, 30 seconds |
|
| 30:37 | answer the question and if you have fake it to make it, do |
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| 30:40 | think you could fake it to make ? Probably? Yeah. Yeah. |
|
| 30:48 | anyway, so I want you not be afraid of the language of |
|
| 30:54 | All right, there's only stuff like I said, there's over 600 |
|
| 30:58 | , there's around 600 skeletal muscles in body. I think you guys ultimately |
|
| 31:03 | like or memorize, have to learn 100 of them, you know. |
|
| 31:07 | if you know what the nomenclature comes , it makes your life easy. |
|
| 31:13 | right. Don't make it harder for . Don't make it difficult just because |
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| 31:17 | should be, feel like it should a difficult subject. Doesn't mean it |
|
| 31:20 | to be. All right. So gonna go back to the physiology for |
|
| 31:27 | moment and we're gonna deal with how work. Muscles are levers. All |
|
| 31:34 | . When we say a lever, is a lever? Well, a |
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| 31:37 | is a straight armed stiff object that along a fixed point which we call |
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| 31:43 | full crumb and it moves something on uh on that uh stiff point. |
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| 31:51 | side of the lever on either side the full crumb is referred to as |
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| 31:54 | movement arm. So this is a arm, that's a movement arm. |
|
| 31:58 | whole thing is the lever will have applied force on one of the |
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| 32:03 | arms will have a resistant force on other one. And what I don't |
|
| 32:07 | about these pictures ever is that they're the direction of the force, |
|
| 32:11 | And for your purposes, that's kind confusing, right? Because it's saying |
|
| 32:16 | weight of this is coming downward, ? And so if I want to |
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| 32:20 | the weight that direction, what am going to do? I'm going to |
|
| 32:24 | downward, right. So just think a lever, what am I trying |
|
| 32:28 | do? I'm trying to move this so that it goes that way. |
|
| 32:32 | right. But what they're dealing with these pictures is they're talking about |
|
| 32:37 | which direction is the resistant force, resistant force is this direction. And |
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| 32:42 | to move it away from the point resistance, that direction I apply the |
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| 32:47 | downward, right? So that's why going like so right now in your |
|
| 32:55 | and I should point out. So a mechanical, even when the load |
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| 33:00 | gonna be near the fulcrum. All . So the closer you get to |
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| 33:04 | fulcrum, the better, the the, the more the less work |
|
| 33:08 | gonna have to do. I think was Archimedes. I want you |
|
| 33:12 | one of those famous, you discoverer philosophers back in Greek who basically |
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| 33:17 | , give me a lever, uh me, you know, give me |
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| 33:20 | lever of infinite size and I can the world, right? The idea |
|
| 33:26 | there is mathematics behind this that you know, if I want to |
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| 33:30 | something really, really big, I have to make a longer lever and |
|
| 33:34 | apply the same amount of force because the way that the levers work. |
|
| 33:38 | kind of cool right now in your , you can think about it like |
|
| 33:44 | . My bone is the lever, joint is gonna be the full curb |
|
| 33:52 | my muscles are going to be the force. OK? Now, this |
|
| 33:58 | where it gets wonky because that is simple model bone joint muscle, but |
|
| 34:08 | are different kinds of levers. All , we have first class, second |
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| 34:13 | and third class levers. When we of levers, we think primarily of |
|
| 34:18 | class levers. And you can see there, there's my weight, there's |
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| 34:21 | full chrome, there's my the force gonna apply to move the weight, |
|
| 34:27 | ? So that's how you think of , right? And an example of |
|
| 34:30 | would be uh like, you pliers when I squeeze on the |
|
| 34:35 | when I apply the force that's gonna up the resistant force thing is we |
|
| 34:42 | have a lot of these types of in the bodies. The example of |
|
| 34:45 | of those type of levers would be jaw, right? So your |
|
| 34:50 | the fulcrum would be right here, temporal mandibular joint, the muscles you |
|
| 34:57 | , actually let's not do the let's just do the axis on, |
|
| 35:00 | know, the actual axis, your , right. So if I if |
|
| 35:05 | skull has weight forward and I want lift it up, I'm using muscles |
|
| 35:10 | the back of the head. My , my axis is my vertebrae, |
|
| 35:15 | ? So you can see like that would be an example of a |
|
| 35:18 | class leap, right? You could your mandibular joints as well, but |
|
| 35:23 | can't see the muscles quite as Ok. So we don't have a |
|
| 35:28 | of these, another type of lever the second class. And so you're |
|
| 35:33 | , ok, well, this is to be a little bit weird. |
|
| 35:35 | can see this is where I'm applying force. This is the resistance force |
|
| 35:40 | sits in the middle. My full way over here in the front. |
|
| 35:45 | , to visualize this, think of wheelbarrow. All right, you guys |
|
| 35:49 | worked with the wheelbarrow, right? got your wheel up here in the |
|
| 35:53 | , you put all your weight in middle and you lift over here at |
|
| 35:55 | back side and then you can move lot of weight, right. We're |
|
| 36:00 | down a lot of, of, dirt and stuff the last couple of |
|
| 36:04 | , you know, right in the of a drought. You know, |
|
| 36:06 | a really brilliant idea. But my like, hey, I got |
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| 36:08 | they need to live. And I'm , all right, fine. So |
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| 36:11 | am I doing? I'm buying bags dirt, £50 each. I can |
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| 36:14 | £50 at a time, but I move more than one. So I |
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| 36:17 | a wheelbarrow, I can put in into a wheelbarrow and I can move |
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| 36:21 | around. That's easy because the fulcrum me to reduce that resistant force. |
|
| 36:31 | on your body, you have So here again, you can see |
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| 36:35 | my full crumb, my tippy right? The ball of my |
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| 36:40 | my muscle would be my calf and the resistant force is my body |
|
| 36:49 | right? So I weigh a My fulcrum is my toes muscles in |
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| 36:54 | calves. What can I do is can lift myself up. All |
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| 37:03 | I can do this all day because feels good. That's second class |
|
| 37:08 | Again, we don't have a lot these. So most of the levers |
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| 37:14 | our body are the third class All right, third class lever, |
|
| 37:21 | full chrome is over on the opposite . My resistant force is way at |
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| 37:28 | far end. So they're on opposite and then I'm doing my movement, |
|
| 37:34 | applied force in the middle. All . Uh You can think of the |
|
| 37:39 | . But again, the example that using here is a shovel or you |
|
| 37:43 | think of a broom because how many you guys have shoveled stuff right |
|
| 37:47 | A lot. How many of you swept something? All right, when |
|
| 37:51 | sweep and you don't sweep like my , you have one hand up here |
|
| 37:56 | the top of the broom. The you're doing is down there on the |
|
| 38:00 | . And what hand you have is here in the middle. Are you |
|
| 38:04 | this hand for anything? No, stabilizing and you're sweeping this way, |
|
| 38:09 | ? It's the applied forces in the , right? The fulcrum is up |
|
| 38:17 | and the resistance forces down there. a shovel can do the same |
|
| 38:21 | I hold the end of the Actually, it's this way because I'm |
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| 38:24 | handed, right. I'm holding the here. I got the other hand |
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| 38:28 | the middle, pushed down and I'm up here and I'm stabilizing over |
|
| 38:36 | That is how most of the muscles here. We are looking at the |
|
| 38:41 | here. You are lifting up the . They're actually making it a |
|
| 38:45 | All right. So what I wanna if I want to lift up the |
|
| 38:49 | , I'm going to contract here, ? I'm applying the force. What |
|
| 38:54 | say the joint was the full the muscle, the bicep is attached |
|
| 38:59 | the bone if you own on the here. So, what am I |
|
| 39:04 | is I'm pulling there and I'm using joint as the point of stabilization to |
|
| 39:12 | the weight, the resistant force. most of your levers in your body |
|
| 39:18 | this third class. You guys think can identify the three different classes, |
|
| 39:27 | draw him out, right? Think this picture. It will keep your |
|
| 39:33 | simple. I practice it when I up on my toes. I'm second |
|
| 39:38 | . Where's my joint? Right? joint is in front of the |
|
| 39:45 | my tippy toes. Whereas my it's between my tippy toes and the |
|
| 39:51 | . What about first class? That's . That's when I think about a |
|
| 39:54 | . That's pretty simple. There are about this part. Mhm. All |
|
| 40:05 | . I spent the next five minutes 10 minutes, spending way too much |
|
| 40:10 | on this topic. All right. apologize for this, but I don't |
|
| 40:14 | why I just want to talk about . More muscle fiber types. We |
|
| 40:18 | leave it as simple as this, . We have two different types of |
|
| 40:22 | types. One of the muscle types has two subtypes. So there's three |
|
| 40:28 | muscle types. We have type one type two A, type two |
|
| 40:32 | The thing that distinguishes them is how they twitch right. In other |
|
| 40:38 | how fast do they create the How much power do they produce and |
|
| 40:43 | fatigue resistant are they? All So if we look at the type |
|
| 40:48 | , the type ones are slow. they take a lot of time to |
|
| 40:52 | their twitch, a lot of time relax. Whereas the type two is |
|
| 40:57 | quick, back and forth. All . So this should be type |
|
| 41:01 | That would be type one. In of power. Type one, they |
|
| 41:05 | produce a lot of force. All . It takes a long time, |
|
| 41:08 | they don't produce a lot of forest two. They produce their force |
|
| 41:11 | very quickly and they produce a larger of force. And finally, in |
|
| 41:17 | of fatigue type ones, they're mostly resistant. Whereas type twos, they |
|
| 41:24 | quick with, when it comes to , they basically burn through their energy |
|
| 41:29 | and they don't have a lot of stamina with regard to how they |
|
| 41:39 | . So the reason type one and two have different fatigue resistance is how |
|
| 41:45 | make their energy. Type one is in nature. So we call type |
|
| 41:51 | cells, oxidative cells. All They produce more A TP. If |
|
| 41:57 | produce more A TP, you have energy to use. And since you're |
|
| 42:00 | , it doesn't take as long. mean, it takes longer to burn |
|
| 42:02 | that energy. So that's why you greater fatigue resistance when you're glyco in |
|
| 42:10 | . All right. That's the type , you do not go to oxidative |
|
| 42:14 | , you're stuck just with that anaerobic . So you make very little A |
|
| 42:20 | . So you burn through the very A TP very quickly, you don't |
|
| 42:24 | enough to keep yourself going. So run out of energy very quickly. |
|
| 42:27 | you fatigue quickly. I throw this here just for giggles. All |
|
| 42:34 | you can look at this if you to and find out the types of |
|
| 42:38 | types that go with. What type things? All right, because I |
|
| 42:42 | get people to ask that this slide different than your slide. Can you |
|
| 42:50 | at this slide and tell me how different? Look down at chairs, |
|
| 42:58 | at this one. Do you see difference colors? Yeah, I was |
|
| 43:04 | at this this morning. So the you have is a picture that I |
|
| 43:08 | from some place and I was looking this, I'm like these colors are |
|
| 43:12 | and it really upset me. So had to make my own so that |
|
| 43:16 | wasn't backwards. All right, because you look at those colors, they |
|
| 43:20 | match what a muscle normally looks Now, this is where I start |
|
| 43:26 | big fight in the classroom. How you guys, how many of you |
|
| 43:29 | like uh when you're eating like like chicken turkey, how many of |
|
| 43:32 | guys prefer white meat? How he dark meat? Which one's better? |
|
| 43:40 | white meat. Why, why? right. Now, the reason I |
|
| 43:51 | up chickens and white and dark meat because when you look at foul, |
|
| 43:57 | , their mussels are divided into the meat and the dark meat. But |
|
| 44:02 | I cut up a human serve one that'd be very, very offensive |
|
| 44:05 | gross and horrible. You know, like a little can cannibalism. |
|
| 44:10 | But you'd see that the meat that made of, the mussels are a |
|
| 44:15 | meat. We don't have white meat dark meat. All right. All |
|
| 44:21 | muscle fibers are mixed together. All . So, what that means is |
|
| 44:25 | our muscles are capable of doing both and slow twitch activities and what we |
|
| 44:31 | to do depending upon what we're doing we will recruit whichever muscles are, |
|
| 44:36 | know, that we need at that time. All right. So the |
|
| 44:40 | one is a red muscle, which why I changed the color here. |
|
| 44:44 | right. And you can see type are really, really dark. The |
|
| 44:48 | two A is also a type of muscle. It's actually a little bit |
|
| 44:53 | though. And then we have the ones. Those are the type two |
|
| 44:57 | , that's the white muscle. So can see here is the dark |
|
| 45:00 | there's the light meat and it's all in. Now, why do I |
|
| 45:04 | this out? Why do we Well, in terms of activities, |
|
| 45:11 | ? This type of muscle type one said remember is slow and oxidative, |
|
| 45:16 | twitch. All right. If I type one muscle, I can use |
|
| 45:21 | muscle to prevent me from getting tired whatever activity I'm doing. Right. |
|
| 45:26 | , if I'm walking, if if I, all I have are |
|
| 45:30 | type two si would tire out pretty and then I just have to lie |
|
| 45:34 | and, and, and die. . Well, a rest. |
|
| 45:40 | If all I have are type when Shasta jumps out of the |
|
| 45:44 | I'm not going to be able to . Right. Birds use a different |
|
| 45:49 | . They fly so they can escape different ways. So they have the |
|
| 45:54 | separated out because of those different types evolutionary strategies. All right. But |
|
| 46:01 | red mussel has lots and lots of . What do we say? Myoglobin |
|
| 46:06 | related to hemoglobin. And it's what that red color, the darkness to |
|
| 46:14 | meat. Hence why your cells over are so dark whereas we don't have |
|
| 46:19 | lot of myoglobin over here, So not so much red, which |
|
| 46:27 | why we're kind of white. we're gonna come back to this in |
|
| 46:31 | a second. I throw this up just to remind you that remember in |
|
| 46:34 | to create strength or whatever fatigue ability have uh asynchronous recruitment that allows us |
|
| 46:41 | bring in more motor units so that can create greater force to overcome the |
|
| 46:45 | . But the thing is is that you're dealing with muscles, muscles adapt |
|
| 46:51 | upon their usage. Now, these two runners from, I think it's |
|
| 46:57 | Jamaican uh national team. I'm not . Again, I just pulled pictures |
|
| 47:02 | the interwebs. Um, and what have here is the guy on the |
|
| 47:06 | and the guy on the right. guy do you think is the |
|
| 47:08 | Which guy do you think is the ? But which one is on the |
|
| 47:18 | ? The one on the right is sprinter? Ok. Or the |
|
| 47:24 | Yeah, either this is the right? And you can see muscular |
|
| 47:30 | . Right. I mean, he more fit, doesn't he? But |
|
| 47:33 | guy will outrun him, distance wise day long, right? And you'd |
|
| 47:39 | , well, it's because he weighs . No, no, actually it's |
|
| 47:42 | types of muscles both of them have now. Generally speaking, if you |
|
| 47:46 | back to slides and look at that graph, it's like here's a |
|
| 47:49 | here's a marathoner and it shows you particular muscle types ratios and then it |
|
| 47:53 | here's a normal person which is a offensive way to put it because the |
|
| 47:57 | is, is we're not 50 And then, you know, it's |
|
| 48:00 | we have a genetically predetermined sort of type for our ourselves. Ok. |
|
| 48:07 | I'm gonna show this a little bit . But when, um, you |
|
| 48:12 | a slice through a muscle, what gonna see is you will see all |
|
| 48:17 | individual cells and if you work and , what's gonna happen is, is |
|
| 48:22 | will see the number of mild fibriles . All right. So when you |
|
| 48:30 | , when you remember we talked about muscle tone. That is what we're |
|
| 48:34 | at here. So, in this case, the type two, which |
|
| 48:39 | what he has, they hypertrophy everywhere he trains and exercises and prepares to |
|
| 48:47 | a better sprinter. All right, guy, the same thing happened, |
|
| 48:53 | he's a type one. And so muscles look a little bit different because |
|
| 48:58 | don't hypertrophy in the same sort of . Type two fibers have a greater |
|
| 49:04 | for hypertrophy. All right, because have to create greater force and remember |
|
| 49:11 | force results in greater speed, And so your sprinters look like weight |
|
| 49:19 | for the most part. And generally , this type of activity and hypertrophy |
|
| 49:28 | detrimental to aerobic performance. All So your sprinters basically are fatigue because |
|
| 49:37 | don't have their cells that got Were the white cells, right? |
|
| 49:42 | they're not able to produce that aerobic to maintain the speeds that they're trying |
|
| 49:51 | accomplish. All right, there's fewer innovating through there or vascular vascular and |
|
| 49:59 | fatigue a lot quicker now to demonstrate , that we are who we are |
|
| 50:05 | there's not much we can do about . Let's take a look at the |
|
| 50:08 | picture. All right. Again, random people on the internet, I |
|
| 50:13 | said before and after pictures. All . And I use two guys because |
|
| 50:17 | tone is easier to see. All . So we got dad bod over |
|
| 50:21 | , you know, he got on juice or the shakes, whichever. |
|
| 50:27 | you can see muscle tone right We got the £90 weakling. He |
|
| 50:33 | on the juice and he still looks a £90 weakling. All right. |
|
| 50:39 | it's not true. He doesn't look now you can tell he's much more |
|
| 50:42 | , isn't he? Right. But the different body types here, he |
|
| 50:47 | turn into that. And the reason that is because this person here is |
|
| 50:52 | type two body type, whereas this is primarily a type one. All |
|
| 50:58 | . No amount of exercising and work ever give him a body like this |
|
| 51:03 | he doesn't have the muscle type. guy would be an incredible sprinter or |
|
| 51:08 | sprinter, incredible long distance running. probably great at any type of activity |
|
| 51:13 | requires type one muscles. This one the other hand, you know, |
|
| 51:20 | exercised, he's just gonna get bigger bigger like the Hulk, he'll never |
|
| 51:25 | thin like this. He's gonna basically his life between those two states. |
|
| 51:31 | he'll get like this and then he'll married and then he'll go back to |
|
| 51:34 | . Ok. So any type of that you do is going to lead |
|
| 51:44 | the um, uh you know, , it's gonna, it's gonna benefit |
|
| 51:50 | muscles, it's gonna strengthen the it's gonna cause hypertrophy. But what |
|
| 51:55 | gonna do is that it fixes that , that or not fixes it, |
|
| 52:00 | enhances the, the primary type of that you have so he could |
|
| 52:06 | He, I mean, again, may have been doing the same type |
|
| 52:09 | workouts that this guy did, but doesn't have a lot of type |
|
| 52:11 | So it doesn't give him the same of tone. If you're type |
|
| 52:19 | you're type one. If you're type , you're type two and that's kind |
|
| 52:22 | the end of it. All you can train a sprinter to have |
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| 52:28 | stamina and to run longer lengths, they'll never be able to do, |
|
| 52:32 | with someone who's a perfect type one makes sense and vice versa. You |
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| 52:36 | someone who has great aerobic activity but never be the best sprinter. You're |
|
| 52:42 | stuck in your category, but you be the best at whatever is in |
|
| 52:46 | category. That's ok. So what you swim all the free time? |
|
| 52:53 | you do the 1600 m? So which one are you better |
|
| 53:01 | It? Varies. Mhm. So what I would say is you |
|
| 53:13 | are more balanced in terms of your type, right? So this is |
|
| 53:18 | uncommon, right? But if you about someone who's a really good |
|
| 53:22 | like you just said, they don't the long distance because they fatigue about |
|
| 53:26 | through. Right. You get in and you're just like, I'm slow |
|
| 53:29 | steady and I can keep this It doesn't have to be 1600 |
|
| 53:32 | You could probably do 3200 m. . You could probably do 4800 |
|
| 53:37 | It wouldn't be fun. But you , I mean, we're, now |
|
| 53:40 | talking like we're talking triathlon level type swimming. Right. Right. I |
|
| 53:46 | , well, no, I'm I'm the Iron Man is, is |
|
| 53:50 | to the five K swimming. I . I can't remember exactly. |
|
| 53:54 | My, my swim, my I told you, I don't know |
|
| 53:57 | I told everyone in the class, I did, I mentioned to the |
|
| 53:59 | , my friend who became the triathlete like a ran like a, I |
|
| 54:04 | know, like a duck. It terrible. Yeah. Well, |
|
| 54:12 | not so much your metabolism is, , it's actually kind of interesting. |
|
| 54:17 | a huge study that was done a of months ago. I mean, |
|
| 54:20 | it was like a meta study. took all the studies and put them |
|
| 54:23 | and said, what do all the tell us? And first off is |
|
| 54:27 | more or less stays constant over the of your lifetime. So it's not |
|
| 54:30 | you have, you know, as get older, it's not like your |
|
| 54:33 | slows down. What happens is, , what happens is, is we |
|
| 54:37 | more sedentary. So it's really the of activity that, that matters. |
|
| 54:43 | , you know, if you're gonna sedentary for the most of your |
|
| 54:46 | guess what? Um your body's if you keep consuming at the same |
|
| 54:50 | your body's gonna say. Well, don't know what to do with |
|
| 54:52 | Oh, I'll just go put it the fat and then that's when life |
|
| 54:55 | . All right. It's not like younger and, you know, you |
|
| 54:58 | better than I do. It's you're more active. You guys stay |
|
| 55:02 | later, you party more. You're , woo fun exercise. Let's |
|
| 55:07 | Let's go throw the frisbee. Let's hacky sack. Let's go do shots |
|
| 55:12 | Mexico where all that stuff scares Now, I'm old and feeble and |
|
| 55:16 | to leave my house. Yeah, know. All right. So what |
|
| 55:25 | resistance and sprint training do? basically, it is going to aid |
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| 55:30 | making your type two muscles grow How does it do so? |
|
| 55:36 | it basically increases cytoplasmic density. All , that's fancy for saying, making |
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| 55:41 | mild fibrils. When you make more fibros, your muscles are going to |
|
| 55:44 | bigger, that's going to make the function better. It's going to give |
|
| 55:47 | a better expression of strength. So other words, you actually see yourself |
|
| 55:52 | being able to work more and lift . Why? Well, you're going |
|
| 55:59 | see an increase in the number of reticulum, you're going to see more |
|
| 56:04 | tubules appear and that means you're gonna greater calcium release, which means greater |
|
| 56:10 | . All right. The other thing you also delay fatigue. It doesn't |
|
| 56:13 | you don't, don't reduce fatigue or rid of it, you still have |
|
| 56:17 | , but you delay it and you up with greater endurance. Right. |
|
| 56:23 | what exercising does. So, you , if you want to get stronger |
|
| 56:29 | training is the way to go when dealing with aerobic endurance, what you're |
|
| 56:33 | now is you're primarily focusing on the one muscles. All right, because |
|
| 56:38 | you're dealing with that endurance, you're reducing fatigue ability. All |
|
| 56:43 | So you increase aerobic capacity of the muscle. What, what does that |
|
| 56:47 | ? Well, it means you can the same amount of, for performance |
|
| 56:52 | the same amount of intensity and it take as much effort to do. |
|
| 56:57 | . So think about right now, , if I tried to run a |
|
| 57:03 | , um, I'd probably kill over about the quarter mile point, |
|
| 57:07 | you know, or I'd at least praying for death at that point. |
|
| 57:11 | . But if I trained and kept it and kept doing it, kept |
|
| 57:14 | it, I could actually run the with the same sort of intensity as |
|
| 57:18 | could, a quarter mile and probably away with it and not feel like |
|
| 57:22 | dying. Ok, maximum aerobic basically, I can do the same |
|
| 57:28 | with, um, um, the effort. So that's what you do |
|
| 57:32 | you exercise and you practice doing those distances. It basically is like, |
|
| 57:37 | the same effort. You know, I do a half mile versus a |
|
| 57:40 | swimming, you know, it doesn't harder, right. So that would |
|
| 57:44 | the example here. So we talked increasing the size of the type one |
|
| 57:48 | . It does make the muscles They just don't hypertrophy in the same |
|
| 57:53 | . All right. So aerobic people fit, they just have different muscle |
|
| 57:58 | . So that type one just doesn't as big looking. And lastly, |
|
| 58:02 | does this uh impede or get in way of the fatigue? How does |
|
| 58:06 | get in the way of that? , simply what I'm doing is I'm |
|
| 58:09 | in more capillary. So I'm providing nutrients and the cells are producing more |
|
| 58:15 | . This mitochondria divide multiply. So able to produce more a TP, |
|
| 58:19 | a TP, gives more energy, energy allows the cells to do the |
|
| 58:22 | thing that they're doing without fatiguing. right. So now we know we |
|
| 58:27 | to exercise. What happens if we exercise, what happens if we live |
|
| 58:34 | lifestyles, we look like the guy South Park. No, we don't |
|
| 58:40 | , but it could happen. But is an example here. This, |
|
| 58:43 | , I think this is a really example. And this is the person |
|
| 58:46 | wore a cap or wore a cast their leg, right? So here |
|
| 58:50 | can see where the cast was. a normal leg that's working when you're |
|
| 58:54 | a cast, the cast is doing work that your, that your leg |
|
| 58:58 | normally be doing right. So your is what's kind of bouncing and lifting |
|
| 59:02 | up. And since you're protecting that calf shrinks down because it's no longer |
|
| 59:06 | , it goes through a period of . And you can see a reduction |
|
| 59:11 | the muscle size. You don't see tone that you would see here and |
|
| 59:15 | not able to produce the same amount power. Now, this is a |
|
| 59:19 | event, atrophy is simply, your is saying, I don't want to |
|
| 59:24 | energy on something that you're not right. It's kind of like paying |
|
| 59:29 | all the streaming services you don't use some point. You're going to say |
|
| 59:32 | tired of my money going some place I'm not using, right? So |
|
| 59:35 | gonna withhold your money and you're gonna it on things that you want that |
|
| 59:39 | to go to that you would So that's your body saying I'm not |
|
| 59:43 | spend the energy, all right. if you lose those muscles, I |
|
| 59:51 | , if you don't use them at , your body is eventually that muscle |
|
| 59:54 | gonna die. It's gonna atrophy to point where it then goes into uh |
|
| 60:01 | uh not, it's not necrotic, in essence, what will happen is |
|
| 60:06 | it will basically die away. And what we said is, these are |
|
| 60:09 | muscles don't increase the number of cells grow and shrink based on the number |
|
| 60:14 | , of fibr inside them. So you lose the cells. You now |
|
| 60:19 | lost the ability for that activity in muscle. Now, to get to |
|
| 60:25 | point, that's pretty far away. not like watching TV. All |
|
| 60:29 | Ok. That's much worse. All . So that's in the muscles. |
|
| 60:37 | any questions about the muscles? All . We got questions today. |
|
| 60:41 | we'll go there and then we'll go . Yeah. Was actually called. |
|
| 60:56 | the muscles won't actually go and I mean, in other words, |
|
| 61:01 | of it like this. If you oh trying to think of a situation |
|
| 61:07 | this, where it's actually so someone has zero activity, say you're |
|
| 61:12 | All right, or say you have you're paralyzed from the waist down. |
|
| 61:18 | going to happen is, you your body is gonna say there's muscles |
|
| 61:21 | even there, it's not even worth . So what it's gonna do is |
|
| 61:25 | cells will eventually die off. If not providing them nutrients, now, |
|
| 61:29 | not going to lose all the muscle , you'll still have nerves that are |
|
| 61:32 | them. Um But in essence, you know, if a cell dies |
|
| 61:37 | that axon would actually withdraw, remove motor neuron that actually innervates it. |
|
| 61:44 | so the thing that we have to or we're going to distinguish here in |
|
| 61:46 | little bit is the difference between a neuron and a and a motor |
|
| 61:51 | one that detects versus one that And so in this case if a |
|
| 61:55 | disappears, you're not going to send signal to where there is no signal |
|
| 61:58 | be received. Uh-huh. Uh-huh. it. Mhm. Right. Turning |
|
| 62:13 | time it's not, no, what it is is basically taking the |
|
| 62:18 | two that you have and making them . Right. You know, if |
|
| 62:22 | want to get cut, yeah. those type shoes that you have. |
|
| 62:28 | . But again, I'm just gonna back and show the pictures of the |
|
| 62:30 | guys. Right. I mean, he's, he's more cut, he's |
|
| 62:36 | fit. But, you know, mean, when I work out |
|
| 62:45 | it's frustrating because I want to slim . Right? Because I'm, I'm |
|
| 62:49 | big guy. I, I was lineman and a, and a linebacker |
|
| 62:53 | high school. Right. I played . That's the type of body type |
|
| 62:58 | am. So when I lift weights don't slim down, I get |
|
| 63:03 | I bulk up, I get which, which is upsetting because I |
|
| 63:08 | wanna be fatter. Right. I've the fattest neck you'll probably see. |
|
| 63:13 | I mean, and I've had it high school. I mean, |
|
| 63:17 | you know, give you a I mean, the guys will know |
|
| 63:20 | , you know, when you get fitted shirts, right? My fitted |
|
| 63:23 | are always too big for me because have like, now I have a |
|
| 63:26 | and a three quarter neck. So inches, you want to try to |
|
| 63:32 | me? It's not gonna happen. right, you're gonna have to have |
|
| 63:35 | really big hands. Right. But never be guy on bottom. Never |
|
| 63:43 | roommate in high school or in That was him. In fact, |
|
| 63:47 | was the reason I picked that picture I was like, man, that |
|
| 63:49 | a lot like him. It wasn't . But, you know, I |
|
| 63:52 | to be thin but sadly, always . Yeah. One. Well, |
|
| 64:03 | , no, so it's not so that it's the number of scores because |
|
| 64:06 | , scores are gonna be in the of the, of the, of |
|
| 64:10 | um of the muscle itself, Because they're basically the units along the |
|
| 64:15 | . What we're talking here is that number of fibers within that sarcomere? |
|
| 64:20 | right. So you can think about like this. If each of those |
|
| 64:23 | fibriles inside a muscle fiber is a . All right, we're just using |
|
| 64:29 | now, right? If I have ropes and I'm trying to pull |
|
| 64:34 | you know, I can put all people on those ropes, but the |
|
| 64:37 | of force that all those people can on there is only going to be |
|
| 64:41 | great as the two ropes attached to thing that I'm pulling. So if |
|
| 64:44 | want to create greater force to move item, what do I need to |
|
| 64:47 | ? Not add more people. I to have to add more ropes with |
|
| 64:51 | people, right? So now I create that force. And that's kind |
|
| 64:56 | what the type two s do it's adding more and more ropes. |
|
| 65:00 | so when I add more ropes that up more space, which is why |
|
| 65:02 | muscles get bigger. All right, type ones is basically saying, I'm |
|
| 65:07 | the people who are pulling the ropes they're always going to produce the same |
|
| 65:10 | of force, but they can keep this till the cows come home. |
|
| 65:15 | right, they get the Gatorade and power bars while they're pulling on the |
|
| 65:23 | , help a little bit. All . So what we're gonna do is |
|
| 65:29 | gonna shift gears big time and we're into the nervous system and when I |
|
| 65:35 | we're shifting gears big time, it's we've been spending a lot of time |
|
| 65:38 | about movement and stuff here. And what we're gonna do is we're |
|
| 65:41 | we're going to move into and introduce to the nervous system. And what |
|
| 65:46 | gonna do over the next hour, ? 40 minutes or 50 minutes is |
|
| 65:50 | gonna look at the protections of the nervous system. How does the central |
|
| 65:55 | system protect itself? Ok. But you need to know what are the |
|
| 65:59 | ? I mean, there's a real thing. We've already talked about this |
|
| 66:02 | , but I want to just kind bring it up again. Right. |
|
| 66:05 | nervous system is, is when we at it, we're, we're talking |
|
| 66:09 | how anatomist have kind of broken it . So this is just a, |
|
| 66:12 | tool or a mechanism to help us understand it. All right. And |
|
| 66:18 | we have two basic parts. So said, here's the nervous system, |
|
| 66:22 | create two boxes. We'll throw some are in this box and some things |
|
| 66:25 | in that box. The central nervous is box number one. All |
|
| 66:29 | This is your brain and your spinal , right? So they work in |
|
| 66:33 | same way since they're in the same , they play a role in |
|
| 66:36 | which means processing information, they are control centers. So they take the |
|
| 66:41 | that you give them and then they the outcome of that information, what |
|
| 66:46 | we do in response to this? they, they tell the body the |
|
| 66:51 | . All right. But all they is the processing information has to come |
|
| 66:57 | them or to the central nervous system the brain or the spinal cord. |
|
| 67:00 | information has to leave the central nervous from the brain or the spinal |
|
| 67:04 | And so everything outside of the brain the spinal cord is either coming in |
|
| 67:08 | going out and that is the peripheral system. All right. So these |
|
| 67:12 | the nerves and the ganglia that are outside of the central nervous system, |
|
| 67:18 | ? So their job is to receive from the outside world and inside your |
|
| 67:23 | , send that information up to the nervous system, let the central nervous |
|
| 67:26 | do its thing. And then they the message from the central nervous system |
|
| 67:31 | they send it off to where it to go. For example, you |
|
| 67:35 | , a bug is walking on your , you feel the bug on your |
|
| 67:39 | , you tell the central nervous system walking on my face. Central nervous |
|
| 67:43 | says swat at the bug. So do you do? All right. |
|
| 67:48 | you see here what the processing there's input in processing and output. |
|
| 67:54 | right. So that's that is kind the two separate parts. So it |
|
| 67:58 | it really easy if it's like all gotta do is ask yourself, am |
|
| 68:01 | in the, am I in the or the spinal cord? If I'm |
|
| 68:04 | , then I'm in the peripheral nervous . It's as easy as that. |
|
| 68:08 | are some very basic organizational principles So there is a hierarchy which means |
|
| 68:13 | are areas that we call upper and are areas that are called lower, |
|
| 68:17 | levels are going to relay messages to from the upper level. So what |
|
| 68:21 | would say, for example is that peripheral system would be lower relative to |
|
| 68:25 | central because the information is being sent and sent back down again. All |
|
| 68:30 | . But here's an example. Also in the spinal cord might be processing |
|
| 68:34 | it may send information further on up the cortex of the brain for further |
|
| 68:41 | . So this would be lower. would be upper. All right, |
|
| 68:45 | is the fun part about the central system or, or the nervous system |
|
| 68:48 | general. Think about who you are a moment. Think about your being |
|
| 68:52 | you, you know, you're right? All right. That is |
|
| 68:55 | order thinking. The very fact that can perceive yourself would be an |
|
| 69:00 | upper order activity, I think. , I am all right. There's |
|
| 69:06 | part of your brain called the which we'll talk about a little bit |
|
| 69:10 | that doesn't understand self but does you know, some very basic things |
|
| 69:16 | you, hungry, cold, sweaty, you know, pain, |
|
| 69:23 | sort of thing. That would be lower order kind of processing, |
|
| 69:28 | So those things that it perceives can sent up to higher things. So |
|
| 69:32 | be like, oh, I feel in my toe. I need to |
|
| 69:37 | my toe. I must have stubbed . Oh, look, I hit |
|
| 69:40 | desk, that sort of thing that's versus the lower stuff, which is |
|
| 69:44 | the the other things that we just there. Um Basically, there are |
|
| 69:51 | and functional patterns of organizations. So with similar functions are found in the |
|
| 69:55 | place. We're going to see this and over again when we talk about |
|
| 69:58 | special senses. So visual processing is done here, thinking is primarily done |
|
| 70:04 | here. The sense of smell is a specific location. Hearing is primarily |
|
| 70:09 | temporal lobe, yada yada yada. basically information and processing is grouped |
|
| 70:16 | All right, the brain and the cord are not simply a bunch of |
|
| 70:21 | or neurons jammed in there and hopefully will work. All right, there |
|
| 70:27 | topographical organization meaning that there is order the point where you can literally point |
|
| 70:34 | very specific sections and say, oh part of the brain right here is |
|
| 70:39 | for uh the sense of touch in shoulder. Whereas the sense of touch |
|
| 70:46 | my knee is way over here and can look at every single person and |
|
| 70:50 | exactly the same. So there's it matches the way your body is |
|
| 70:56 | . And finally, the central nervous is plastic. That means there are |
|
| 71:00 | changes that are taking place that basically and create your brain. In |
|
| 71:07 | the fact that you're sitting here listening me and internalizing this demonstrates the plasticity |
|
| 71:12 | your brain, right that you are on information, new information, creating |
|
| 71:17 | neural networks is an example of the that the central nervous system actually uh |
|
| 71:26 | . OK. So these are principles we're gonna be using over and over |
|
| 71:29 | over again. I'm not gonna ask what are the four principles or |
|
| 71:32 | blah, blah. It's as we through, you're gonna say, oh |
|
| 71:34 | it is again, here it is , here it is again. So |
|
| 71:37 | you learn the organizing principles as you into a new part of the brain |
|
| 71:40 | a new part of the system, be like, ok, well, |
|
| 71:42 | is stuff that I've already seen. , it's just specific for this particular |
|
| 71:47 | . Now, the central nervous system divided into two parts right now, |
|
| 71:53 | , what we're doing is we're looking , you know, you can imagine |
|
| 71:57 | are cutting up on the brain for first time and they notice we have |
|
| 72:00 | dark areas and we have light All right. And so they named |
|
| 72:04 | gray and white. All right, it's not really, it is kind |
|
| 72:08 | grayish, it's not this brown mushy that you see up here. It's |
|
| 72:11 | of a kind of a gray when would fix it. Uh And what |
|
| 72:16 | say is, all right. what is gray matter? Well, |
|
| 72:18 | matter is primarily the cell bodies of . All right. So it's where |
|
| 72:23 | bodies are actually found together. And you can see these are, this |
|
| 72:28 | the whole central nervous system, So, here's your brain and your |
|
| 72:31 | cord up there. This is the that's part of your brain. This |
|
| 72:36 | here is the cerebellum that's part of brain that's back here. And what |
|
| 72:40 | doing is saying here, I'm cutting here, I'm cutting here. I'm |
|
| 72:43 | downwards. So now I'm looking primarily this is the part of the brain |
|
| 72:46 | , the medulla and then down this is a cut through the spinal |
|
| 72:50 | , but we could have cut anywhere you can see this pattern of gray |
|
| 72:53 | white throughout the entire structure. So here, you can see we got |
|
| 72:58 | on the outside and then we got parts on the inside that are gray |
|
| 73:02 | then there's white in between all So when you look at the |
|
| 73:05 | it's gonna be gray, white, . So it's kind of like an |
|
| 73:08 | the whites in the middle, Um Here in the cerebellum, same |
|
| 73:12 | of pattern, you see gray on outside, white on the inside and |
|
| 73:15 | more gray on the inside, But then as you move further |
|
| 73:21 | the gray is mostly just inside with surrounding it. And here you can |
|
| 73:25 | white and here's the gray on the . And so this pattern is kind |
|
| 73:30 | a repeatable pattern over and over gray is central, then white and |
|
| 73:34 | as we move further up, we're to add gray on the outside one |
|
| 73:37 | time. And so what the gray , is simply those areas where you |
|
| 73:41 | cell bodies. All right. It mean that there aren't axons, |
|
| 73:45 | there are gonna be some axons, they're gonna be moving outward. And |
|
| 73:48 | the white matter represents the axons. the white matter is points where information |
|
| 73:55 | traveling either outward, upward or right? Or it's cross like what |
|
| 74:01 | doing over here. All right. way to remember this is we talked |
|
| 74:08 | myelin. Remember myelin that insulating It's primarily plasma membrane, which is |
|
| 74:15 | lipids and fats lipids are primarily right? When you go and buy |
|
| 74:22 | at the store, the white part the fat. That's an easy way |
|
| 74:26 | I can remember it. So myelinated white matter gray matter are where |
|
| 74:31 | primarily see the cell bodies clustered together we're looking at um, areas that |
|
| 74:38 | internal. Like here, here, know, like in there right |
|
| 74:42 | those clusters of gray matter that's referred as nuclei, we just call them |
|
| 74:53 | . So there are four different types protections, right? Because your brain |
|
| 74:59 | not this hard structure. Have you left butter out, you know, |
|
| 75:07 | the table, right? Not just before you cook. And so |
|
| 75:11 | it's hard now I'm talking like overnight keeps its shape. But if you |
|
| 75:16 | it, that is the texture of tissue, right? It, it |
|
| 75:24 | mushy. It is gross and And that, how do I |
|
| 75:29 | Well, I used to work on and we'd have to sacrifice them to |
|
| 75:33 | tissue one time or two. I'd to have brain and I'm like, |
|
| 75:37 | , I'll just pull out the It's the worst thing ever. It |
|
| 75:41 | , it was like this butter you grab onto it. It just falls |
|
| 75:44 | . It's like, it's like, , like fat, right? Soft |
|
| 75:50 | , it's held in position and keeps shape because of the protective structures that |
|
| 75:57 | it, which is kind of And what we do is when you |
|
| 76:01 | work on a brain, I don't if you guys get to play with |
|
| 76:03 | , a brain in the lab. you guys, do you guys know |
|
| 76:08 | brain? All right, you gotta sheep brains. All right. What |
|
| 76:12 | done is when they, you sacrifice those animals and they're pulling out |
|
| 76:17 | organs, they fix the organs in usually. All right. So it's |
|
| 76:22 | and alcohol. It's a mixture and water, right? And so it |
|
| 76:27 | the shape that it has because you've made everything solid. So you'll get |
|
| 76:34 | play with the sheep brains. So , they're pretty cool. All |
|
| 76:38 | what we have here is we have different protections. There's four different types |
|
| 76:43 | protections. We're going to see the , which we've already talked about and |
|
| 76:46 | vertebrae, which we talked about. we're not gonna talk about them |
|
| 76:49 | They're hard. All right. It's the outside. Then we have these |
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| 76:53 | membranes are called the meninges and then the meninges or within the meninges, |
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| 76:58 | going to have cerebral spinal fluid. then the other characteristic that isn't going |
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| 77:02 | be shown in this picture is something the blood brain barrier. All |
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| 77:06 | we're just gonna walk through all three them and we're gonna start here with |
|
| 77:08 | meninges. All right. These are protective membranes so you can see them |
|
| 77:14 | . Um There is, I'm trying just see where they are. Here's |
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| 77:17 | p of the Rano the dura. right. So they're the two purple |
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| 77:21 | there's one little brown, one down on the bottom right now, the |
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| 77:25 | form. So if you can ever across this term, Mannix, it's |
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| 77:28 | referring to one of the meninges. the singular form. So it's just |
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| 77:32 | weird word right now. The truth , is the way that you look |
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| 77:36 | this stuff is you go from the to the inside. And so outside |
|
| 77:40 | be dura middle would be arachnoid inside is the pia. But you can't |
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| 77:45 | acronyms with, with that because Dap make any sense. If you go |
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| 77:49 | opposite direction, you have a pad the peas on the inside, the |
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| 77:54 | and the middle of the dura on outside. That's how I remember |
|
| 77:57 | If you can't do the pad, don't worry about it. But I'm |
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| 78:00 | flip it around. I'm gonna work the inside, I'm gonna work |
|
| 78:03 | OK. So that we can focus the pad that protects. So the |
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| 78:08 | matter is the layer nearest the brain , the nervous tissue, all |
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| 78:14 | And so it follows all the it goes down deep, it comes |
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| 78:17 | out again. It is literally It's very, very thin, |
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| 78:22 | very delicate. You have blood vessels are actually working their way through that |
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| 78:26 | they, those blood vessels then will deep into the brain tissue. So |
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| 78:30 | would be the PM matter. So highly vascularized closely to, here follows |
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| 78:34 | the contours, very thin. All above that. You can see here |
|
| 78:40 | go up a little bit. This the arachnoid matter. When you hear |
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| 78:43 | word arachnoid. What do you think spiders? Good. All right. |
|
| 78:48 | reason it's called the arachnoid matter is between the arachnoid matter and the PM |
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| 78:54 | , there is a space called the space and it has all these little |
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| 79:00 | . In other words, little tires basically separate out those two structures and |
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| 79:04 | all filled with cerebral spinal fluid. right. And it looks like these |
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| 79:09 | these little trabecule. If you pulled out, it looks like a spider |
|
| 79:13 | . And I, the way I this is this is where the brain |
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| 79:15 | live. You have brain spiders. you ever been walking around? You |
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| 79:21 | into a room and you're like, don't know why I came in here |
|
| 79:25 | the brain spiders ate a neuron. cheesing. That's not how it |
|
| 79:30 | All right. But that's what that's my excuse. You know, |
|
| 79:35 | you got the little brain spiders live the brain space now it's the subac |
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| 79:38 | space. So you have the erect matter, the PM matter, subarachnoid |
|
| 79:42 | in the subarachnoid space. That is you have the cerebral spinal fluid. |
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| 79:47 | right. Now, the arachnoid matter a little bit thicker than the P |
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| 79:50 | matter. And so it has a bit more resistance and it's a little |
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| 79:53 | more protective. But again, you're to see in that subarachnoid space, |
|
| 79:57 | see larger veins and larger arteries traveling before they get smaller and penetrate into |
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| 80:02 | P A. And then ultimately dive into the nervous tissue. The last |
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| 80:06 | , the outermost layer is a really tough layer. All right. |
|
| 80:10 | If you've ever seen Ziploc gallon like the freezer bags, they're pretty |
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| 80:15 | , aren't they? You can pull them and they don't stretch, |
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| 80:17 | they're really resistant. That's what the matter is like. And why I |
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| 80:21 | to use the example of the Ziploc is because there are two layers to |
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| 80:24 | dura. All right, the dura they're shown here is one, but |
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| 80:30 | , we have one that's, there's layer that's near the bone, hence |
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| 80:34 | name Perry osteal and the other one next to the Arachnoid. All |
|
| 80:39 | And there's a small space in between , but we're not really focusing on |
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| 80:43 | . And so these two layers, meningeal and the periosteal are basically closely |
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| 80:47 | in everywhere within the uh you surrounding the brain, except for one |
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| 80:53 | area. And it doesn't show in picture. I'm sure I have a |
|
| 80:56 | a little bit, right? There's be some areas where these two different |
|
| 81:00 | separate out and I'm gonna erase this quick so that we can just kind |
|
| 81:04 | show you what it kind of means . No. All right. So |
|
| 81:13 | would happen is you have the dura have one layer like, so this |
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| 81:19 | be periosteal. So that's perry osteal then you'd have the other layer and |
|
| 81:25 | what will happen is that it will out like so and so it creates |
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| 81:31 | space inside that's filled with blood and would be the dural sinus. All |
|
| 81:38 | . So notice it's not the subdural . Subdural would be the space that |
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| 81:43 | underneath, right? So if I'm gonna hatch it like that, so |
|
| 81:48 | a really, really thin space that's below the dura, the dural sinus |
|
| 81:55 | different. And what we're gonna see just a moment, I'm just gonna |
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| 81:59 | my little subur space and here I'm draw my Arachnoid. It's not that |
|
| 82:03 | , but I just want to do . And what you're going to see |
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| 82:05 | there are portions of the arachnoid that outward and open up into that |
|
| 82:12 | OK. We'll get to that in a moment. This would be the |
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| 82:16 | layer right there. This right here be subarachnoid space and then that right |
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| 82:24 | would be P A that helps. know my art is terrible. But |
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| 82:32 | I had seven colors. I would the seven colors. All right. |
|
| 82:40 | number 13 layers that serve as a barrier between the bone and the nervous |
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| 82:47 | . So we got bone, we've these three layers and then that leads |
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| 82:50 | to the next structure which is, is cerebral spinal fluid. If you |
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| 82:56 | at a brain, your brain starts during early development as a tube. |
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| 83:02 | right. And that tube then gets and bent and twisted and stuff. |
|
| 83:08 | so what you end up with is tube that ends up with this kind |
|
| 83:12 | weird looking shape and these weird looking inside the actual cerebrum are referred to |
|
| 83:19 | the ventricles. All right. So neural canal is that tube and then |
|
| 83:25 | is what's left over. Now, a type of glial cell in there |
|
| 83:28 | going to be ependymal cells. We'll to that in a little bit and |
|
| 83:31 | have four of these ventricles. here's the good news. The ventricles |
|
| 83:35 | easily named. It's not 1234, it might as well be. All |
|
| 83:38 | . What we have is we have left and a right lateral ventricle. |
|
| 83:43 | this is my left side of my . So the ventricle on this side |
|
| 83:46 | be the left lateral. See it's hard right now, they're connected to |
|
| 83:51 | other by a small hole called the for ramen. You see what we |
|
| 83:55 | here, the between the ventricle That's what it's called, right? |
|
| 84:02 | you can see here here's the inert for amen. And then what you |
|
| 84:06 | is you form the third ventricle. notice not a one and a |
|
| 84:12 | you got two laterals, two laterals the inter ventricular frame. They open |
|
| 84:16 | into the third ventricle. So now in the middle part of the |
|
| 84:19 | you can see right there, there's third ventricle, it's very, very |
|
| 84:21 | from the front view and then exiting from the third ventricle is the cerebral |
|
| 84:26 | , which is a fancy word for the the tube or the area filled |
|
| 84:30 | fluid going to the next space. in the cerebral Hansen ta cerebral |
|
| 84:36 | The zebra aqueduct opens up into the ventricle. Here you see the fourth |
|
| 84:40 | front view there it is from the view. All right. Now, |
|
| 84:43 | fourth ventricle has three openings, it two on the on the sides. |
|
| 84:49 | are the lateral apertures. And then has one that is called the medial |
|
| 84:53 | , which is going to be located that way. It's not shown in |
|
| 84:56 | picture. All right. And then those three openings below that, that |
|
| 85:03 | continues on downward and continues going and becomes the central canal and the central |
|
| 85:09 | is part of the spinal cord. if I went back, trying to |
|
| 85:16 | how many pictures you can see there's the central canal there's your fourth |
|
| 85:22 | , right? There's part of the ventricle, there's your lateral ventricles. |
|
| 85:26 | is parts of the lateral ventricles. you can see them all in |
|
| 85:34 | Now, why do we bring up ventricles? Well, this is where |
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| 85:37 | spinal fluid is going to be And cerebral spinal fluid is, is |
|
| 85:42 | clear, colorless liquid. It's actually from the blood. All right, |
|
| 85:46 | circulates in the ventricles. So it's up here in the laterals. It's |
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| 85:50 | here in the third, it's made the fourth. It goes out through |
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| 85:52 | apertures and it empties out into that space and then that fluid and it |
|
| 85:58 | on down through the central canal. this layer of cerebral spinal fluid completely |
|
| 86:03 | the brain and it sits between the and the arachnoid matter in that subarachnoid |
|
| 86:08 | . So it fills up that but it's flowing and it constantly moves |
|
| 86:12 | it has three characteristics that are important its protective function. It has |
|
| 86:18 | it provides specific protection in terms of and it provides environmental stability, which |
|
| 86:25 | more of a physiological protection than an protection. When we talk about |
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| 86:31 | the the cerebral spinal fluid has the density as the brain. So if |
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| 86:36 | take the brain and you put it cerebral spinal fluid, it doesn't sink |
|
| 86:40 | it doesn't rise, it just sits right, kind of cool. All |
|
| 86:45 | . If I throw you in a pool? What's gonna happen to |
|
| 86:49 | Are you gonna sink? I don't . I float. Might be all |
|
| 86:55 | fat. Yeah. If you don't any fat you're going right to the |
|
| 86:59 | . All right. I'm buoyant. . I go to the top. |
|
| 87:03 | have a swimming pool in my back . I'm trying to scrub the |
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| 87:06 | Have to swim down there and scrub bottom and I can stay down there |
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| 87:09 | like two seconds because the moment I the, pushing me back up to |
|
| 87:12 | top drives me nuts. All But this is a really good feature |
|
| 87:17 | what it does is it provides an . So the brain doesn't get pulled |
|
| 87:21 | by gravity. It reduces the brain's by 95%. And so the brain |
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| 87:28 | basically sitting on a pillow of fluid and surrounded by fluid. And so |
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| 87:34 | doesn't slam down at the bottom of skull and then ooze down the frame |
|
| 87:38 | Magnus, which is what it would to do if it didn't have or |
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| 87:43 | you didn't have this buoyancy associated with it. Now, this is |
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| 87:50 | a non compressible fluid, water for most part is non compressible. All |
|
| 87:55 | . And so what this does is fixes the brain in the center of |
|
| 88:00 | cranium. It's not pressed up against wall, it's not sitting on the |
|
| 88:04 | of the floor of the cranium. basically sits there. And so it |
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| 88:08 | as a shock absorber. You could this all day long and it doesn't |
|
| 88:11 | the brain, right. If you to move the brain, you have |
|
| 88:15 | do quite a bit of force to it move within that space because it's |
|
| 88:21 | hard to compress it. So it kind of as a shock absorber. |
|
| 88:27 | finally, in terms of stability, we can do is we can move |
|
| 88:30 | and waste both to and from the . It doesn't do it directly, |
|
| 88:35 | does it indirectly. But by by this near association with the nervous |
|
| 88:41 | what you can do is if there any sort of uh slight fluctuation, |
|
| 88:46 | can move materials in or out very quickly into the surrounding fluid. |
|
| 88:52 | so that provides a physiological protection and ensures that the surrounding nervous tissue or |
|
| 88:59 | the environment surrounding the nervous tissue stays or less constant. And this is |
|
| 89:05 | you also move materials between one of ways to move materials between the brain |
|
| 89:10 | the blood that surrounds it. where it comes from, it's going |
|
| 89:14 | form in these three really in the laterals of the third and the |
|
| 89:18 | there are these regions that they're being here. These are called the choroid |
|
| 89:21 | . These are highly vascularized regions. here the blood vessels get right up |
|
| 89:25 | the surface and they actually allow you these cells, the upend dial cells |
|
| 89:30 | pull materials from the blood and to the cerebral spinal fluid, this is |
|
| 89:35 | a comparison. So you can see mostly water, right? And it |
|
| 89:39 | a couple of other things that it from the blood, but it looks |
|
| 89:43 | lot like the plasma, there are slight differences, but apart from those |
|
| 89:48 | differences, it is very, very . All right. So most of |
|
| 89:55 | stuff that goes in there is either to go by simple diffusion or you |
|
| 89:59 | to help it get along. In words, you have to have the |
|
| 90:02 | carriers. So if you're not you're not going to be moved in |
|
| 90:10 | to look here any bottled water. , bottled water. Can you lift |
|
| 90:14 | your bottle real quick? So that a half a liter of fluid? |
|
| 90:18 | right, 0.5 liters 500 mils your produces or your, well, let |
|
| 90:25 | say your total volume of cerebral spinal surrounding the brain and down through the |
|
| 90:29 | is about 100 and 20 to 150 . 100 and 25 times four is |
|
| 90:36 | . Your body produces 500 mils a . So you actually replace your cerebral |
|
| 90:40 | fluid four times daily. And it's that, that's the volume. So |
|
| 90:45 | quarter of that volume is how much surrounding your brain. Now, wait |
|
| 90:49 | second, I'm replacing it. So that means is I'm making it |
|
| 90:54 | I'm flowing through and then out and and I have to be flowing |
|
| 91:00 | OK. So where am I Well, I flow through the four |
|
| 91:04 | and out down through the tubes and through the apertures around through the reno |
|
| 91:09 | . And then that subarachnoid space, I said, has these penetrations, |
|
| 91:14 | granulations so that fluid flows outward and exits out into the blood in these |
|
| 91:21 | sinuses. So what I borrowed from blood, I returned back to the |
|
| 91:27 | . OK. Now, how does flow work? Well, first, |
|
| 91:31 | I'm making stuff that's going to create and so that's going to be a |
|
| 91:35 | force. But also I have the ependymal cells have SIA so they |
|
| 91:39 | there and go, you go you go away and then the fact |
|
| 91:42 | you have any sort of posture when stand up, when you sit |
|
| 91:45 | when you move around these postural factors to move fluids in your body. |
|
| 91:51 | this is one of the places that does. So this is just a |
|
| 91:54 | picture. So you can see it little bit more closely here. You |
|
| 91:56 | see the granulations up here. So can imagine the fluid was made, |
|
| 92:00 | came down, it went out through aperture, let's say it came out |
|
| 92:03 | aperture around this side, it worked way around up, it goes, |
|
| 92:07 | point of lowest pressure would be And that's where you're driving the fluid |
|
| 92:11 | out it goes through into the dural that blue represents the dial sinus, |
|
| 92:15 | blue. The last protective structure is blood brain barrier. All right. |
|
| 92:23 | here we have two different aspects to blood brain barrier. One, that's |
|
| 92:27 | one that's physiological and this is something protects your brain from receiving materials. |
|
| 92:34 | neither wants needs or wants to stay from. All right. So, |
|
| 92:40 | that the blood is carrying into the or um into the blood into the |
|
| 92:46 | region has to pass through multiple physical in order to get to the actual |
|
| 92:52 | tissue. So what that means is that there has to be mechanisms in |
|
| 92:57 | to allow those things. And what does is it ensures that the environment |
|
| 93:02 | the nervous tissue stays more or less , right? We already talked about |
|
| 93:06 | p for the week contest, What happened when we put too much |
|
| 93:10 | in our body, water went to brains and reduced its ability to do |
|
| 93:14 | activity which killed the poor woman, ? So you can see water which |
|
| 93:20 | not particularly dangerous, although I guess could drown in two inches of |
|
| 93:25 | right? I mean, all you do is lie down face first and |
|
| 93:28 | come up, right? You but generally speaking, I put water |
|
| 93:32 | my body, that's something my body , but it can be dangerous. |
|
| 93:36 | I want to regulate what can come and what can go out. And |
|
| 93:39 | the purpose of the blood brain So there's anatomical aspects to it, |
|
| 93:43 | we're gonna see here. And there's aspects which are dependent upon that |
|
| 93:49 | When we talk about anatomical. First , when we talk about the capillaries |
|
| 93:54 | in the body, the capillaries in bodies have tight junctions, but they're |
|
| 93:58 | leaky, tight junctions. It's one the first oxymorons you get to hear |
|
| 94:02 | , right. So the way you imagine this is if you have a |
|
| 94:05 | of marbles filled with water and you in and you scoop your hands in |
|
| 94:10 | pull out marbles and water. The are going to leak through your finger |
|
| 94:14 | the water is going to leak through fingers. So the marbles stay stuck |
|
| 94:16 | your hand, right? But the kind of escapes in between your |
|
| 94:20 | right? That's an example of how of the capillaries in your body are |
|
| 94:23 | so big things can't pass in between capi areas. But water and other |
|
| 94:27 | things could in the brain, a from the surrounding cells tells those tight |
|
| 94:34 | to be tighter. So and take same fingers now, superglue in between |
|
| 94:38 | . So now you can't separate your and now go scoop again, the |
|
| 94:42 | is going to stay in your All right. So that's an |
|
| 94:46 | You have tight junctions that are actually , they're no longer leaky. The |
|
| 94:50 | thing that you're going to have is going to increase the density of the |
|
| 94:55 | lamina. Now remember basal lamina basement , that's what you see in all |
|
| 94:59 | cells. And so if I make thicker, it makes it harder to |
|
| 95:02 | through, right? You remember we about diffusion. If it's thin, |
|
| 95:06 | to pass through the thicker, it the harder it is through. Third |
|
| 95:09 | and this is the one that you here is the astrocytes. The astrocytes |
|
| 95:15 | the glial cells that are kind of support cells of the nervous system. |
|
| 95:19 | what they're doing is they're wrapping themselves the capillary. So if the pink |
|
| 95:23 | represents the capillary cells at endothelium, purple cells are the astrocytes and what |
|
| 95:29 | doing is they're coming around and they're another barrier of cells. So if |
|
| 95:35 | in the plasma, you have to pass through a capillary cell, pass |
|
| 95:38 | the basement membrane and then pass through astrocyte before you can even get into |
|
| 95:42 | nervous tissue or the surrounding inners So it's just a third layer. |
|
| 95:48 | anything that you want that passes from to there, there to there has |
|
| 95:53 | pass through those cells. So there's literal physiological or anatomical barrier of cell |
|
| 95:59 | top of cell that sits between the and the interstitial fluid of the |
|
| 96:06 | All right. Now, let's say want something right. I don't know |
|
| 96:12 | a glucose molecule. You think your wants glucose? Oh yeah. Think |
|
| 96:17 | how good sugar is when you eat . Does that make you happy? |
|
| 96:22 | , because your brain says give me . That's why you get the happy |
|
| 96:26 | because the brain loves glucose. But can't pass through that cell and it |
|
| 96:31 | pass through this cell unless it has carrier. All right. So this |
|
| 96:35 | now the physiological barrier. Things that water soluble must have a carrier that |
|
| 96:42 | them to pass through. If I'm soluble, nothing's gonna stop me. |
|
| 96:47 | can move wherever I wanna go. , for example, is a fat |
|
| 96:51 | solution. Now, when you drink , does that affect your brain? |
|
| 97:00 | , it does. Why nothing's gonna the alcohol, alcohol is gonna |
|
| 97:03 | I'm gonna go party up here and brain goes party with me and a |
|
| 97:08 | of hours later you're throwing up. ? Because it's also a toxin. |
|
| 97:13 | right. But if you take sugar , you have to have something that |
|
| 97:17 | it along. So water soluble substances to be transported. Water is one |
|
| 97:23 | those weird things where it's small it can move anywhere. It wants |
|
| 97:25 | go moving down uh its concentration gradient via osmosis. But if you're lipid |
|
| 97:31 | , you can go anywhere. So do we have the blood brain |
|
| 97:36 | Well, it's at all the blood in the cerebrum except for some very |
|
| 97:41 | things. Uh you'll have blood brain at the choroid plexus where you're actually |
|
| 97:47 | uh the solution, but it's a bit different. And then we have |
|
| 97:50 | areas of the brain that need to have access to the blood. So |
|
| 97:54 | example, the hypothalamus is a uh a structure that's responsible for regulating many |
|
| 98:00 | in the system. So it needs know what's going on in the |
|
| 98:02 | So it knows how to regulate Um, pal gland is another one |
|
| 98:06 | outputs hormones. Uh Vomiting center. , basically, um, the odds |
|
| 98:14 | you putting something in your body that's to you is likely through consumption, |
|
| 98:22 | ? I mean, you guys live the five second rule. You |
|
| 98:26 | you drop an Oreo cookie, goes the floor, pick it up, |
|
| 98:29 | on it because that makes it better you eat it right? Even though |
|
| 98:32 | rolled through like six spider webs hm. Right. So the odds |
|
| 98:39 | something poisoning you is probably because you foolish enough to stick it back into |
|
| 98:43 | body through your digestive system. Digestive goes to the blood in the |
|
| 98:47 | That's where the toxin is. So says, hey, I found the |
|
| 98:50 | . Um, where did it come ? Probably ate it. Throw |
|
| 98:54 | let's get, get it out out of our bodies. You get |
|
| 98:57 | by a rattlesnake. What do you ? Detect the toxins? What did |
|
| 99:02 | do? You get nauseous and you up, get bit by a black |
|
| 99:06 | . What happens? You get you throw up, your body thinks |
|
| 99:10 | the majority of poisons you put in body are a function of you sticking |
|
| 99:13 | stupid in your body. All So that's a natural response. So |
|
| 99:17 | center is always detecting for things that . Uh The choroid plexus doesn't have |
|
| 99:22 | have a certain degree of permeability so you can produce that CS F. |
|
| 99:25 | the blood brain barrier is less So this just kind of shows you |
|
| 99:30 | uh those types of transport. So what we have with regard to the |
|
| 99:35 | brain barrier is we're gonna have these junctions so we can't pass through |
|
| 99:38 | So um if you're lipid soluble, can pass between cells or three |
|
| 99:43 | We don't care because nothing's gonna stop , right? But if you are |
|
| 99:48 | water soluble, you're gonna have to some sort of carrier that allows you |
|
| 99:54 | move across the cell. If you're gonna be able to just move into |
|
| 99:56 | cell and the back out, you to have carriers all along the |
|
| 100:00 | Another thing you can do is you do something like Tracy tosis where you |
|
| 100:03 | a receptor, you get picked up a vesicle that vesicle then opens up |
|
| 100:07 | the other side and then you're released the other side. So if you're |
|
| 100:10 | drug designer, what type of what do you want, what type |
|
| 100:12 | characteristic would you want your drug? you want it to affect your |
|
| 100:17 | you want to be lipophilic. that's kind of one of the main |
|
| 100:21 | of most of these drugs that uh, that affect the brain is |
|
| 100:25 | have some sort of lipophilic characteristic that's them. So they can pass through |
|
| 100:30 | ease. Otherwise brain's just gonna say , don't care. All right. |
|
| 100:37 | little bit. How are we doing time? Oh, not too |
|
| 100:43 | All right here we're doing some heavy again. All right. And what |
|
| 100:48 | want to do is I want to you some arteries of the brain. |
|
| 100:51 | again, when you look at a like this, they've labeled everything on |
|
| 100:54 | planet and so it can become kind scary. Stop looking at the scary |
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| 100:59 | over here, find the things over , use a highlighter circle, whatever |
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| 101:03 | need. OK. And I'm gonna kind of point a couple of things |
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| 101:05 | here. So the way that you look at the brain is that you |
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| 101:09 | divide the brain into two halves, anterior half and a posterior. So |
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| 101:13 | would be anterior, that would be , right. And so this is |
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| 101:16 | at it from the inferior side. you can see here if I make |
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| 101:19 | dotted line, there's the anterior, a posterior region right. Now, |
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| 101:24 | is a region that I've highlighted here the middle. It's called the circle |
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| 101:28 | Willis. We'll deal with the circle Willis in just a moment. I |
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| 101:31 | point out with the circle of even though we pointed out only 70% |
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| 101:34 | us actually have a circle of So uh we teach it as if |
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| 101:39 | all have it. But um 30% you don't. So there you |
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| 101:45 | Don't ask me which ones. I know, we can flip coins, |
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| 101:48 | guess. All right, with regard the anterior segment, we have first |
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| 101:53 | internal carotid artery. All right. know where your carotid arteries are. |
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| 101:56 | one of those ones that you kind learn as a kid. Yeah, |
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| 101:59 | in your neck and what it does it carries blood up to your head |
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| 102:03 | into your brain. So the internal go in. So you can see |
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| 102:06 | right here, the internal carotid. you can imagine it's coming this way |
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| 102:11 | so and then they divide it and one of them are going to either |
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| 102:15 | and that internal carotid artery splits. right. And so it's going to |
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| 102:20 | the anterior cerebral and the middle So anterior cerebral, middle, |
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| 102:27 | internal carotid splits. There's the anterior , middle, cerebral, internal cro |
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| 102:34 | the middle splits. There's the anterior and the two anterior cerebral arteries join |
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| 102:40 | and form one anterior cerebral. All . So basically two sides come |
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| 102:47 | the front of your brain is fed the anterior cerebral, the middle part |
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| 102:51 | your brain is fed by the middle artery. You see this is not |
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| 102:58 | science. Ok. It seems confusing there's lots of names involved. All |
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| 103:05 | . Now, if you come to posterior segment, you have moving up |
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| 103:10 | vertebrae, two arteries, one on side, you, you, |
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| 103:14 | you're a, a uh mirror right? So here's a vertebral |
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| 103:20 | there's the vertebral artery and they're coming together. All right. And what |
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| 103:24 | gonna do is they're gonna come together join and form a single artery. |
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| 103:28 | again, you're looking at a body way. So this is on the |
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| 103:32 | of the brain. It's called the artery because it's on the basement |
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| 103:37 | the basil side, right? And basal artery then is going to split |
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| 103:44 | . And you're gonna see here is trying to find which one I'm looking |
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| 103:48 | inferior cerebellum. All right. So structure, this big thing right |
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| 103:53 | which we haven't learned yet is called cerebellum. This portion up here is |
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| 103:57 | cerebrum. All right. So when think of your brain, you think |
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| 104:00 | the cerebrum, your little brain in back is the cerebellum, see even |
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| 104:05 | it, right? So what we is we get the inferior cerebellar |
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| 104:13 | All right. So that's what it . One on the anterior side, |
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| 104:15 | one on the posterior side. But is what we're looking at here then |
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| 104:18 | get a little tiny spider legs. going around the brain stem in a |
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| 104:22 | of the brain stem called the So the little tiny spider legs are |
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| 104:26 | ponte arteries. All right. And the next one is the superior |
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| 104:30 | So it comes up and it goes . So those two go around and |
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| 104:33 | on top of the sere bellum. the superior cerebellar arteries, so you |
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| 104:39 | see the posterior side is being fed way. And then finally, the |
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| 104:44 | split is here, that's the posterior arteries. So we have an anterior |
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| 104:52 | , we have the middle artery. it's cerebral, cerebral and then back |
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| 104:58 | in the back, anterior cerebral right? And then with regard to |
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| 105:03 | cerebellum, we have one on we have a pair on top, |
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| 105:06 | have a pair on bottom, inferior superior cerebral or cerebellar and then going |
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| 105:13 | the brain stem around the ponds. the ponte and that's blood coming up |
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| 105:17 | the vertebral arteries to form that Basler . So a lot of other stuff |
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| 105:23 | there, but don't be uh freaked about those yet. Now, to |
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| 105:27 | kind of visualize just the cere or cerebrum, right? You can see |
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| 105:33 | , I've just highlighted the one genos is the anterior cerebral. So remember |
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| 105:38 | is the uh cars, right? internal carrots, middle, anterior, |
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| 105:47 | , middle, anterior, cerebral. then over here, posterior, where |
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| 105:51 | it come from there's vertebral Basler off go and it just shows you how |
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| 105:56 | blood is being distributed along the OK. See circle Willis. So |
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| 106:08 | I said, 70% of us have 30 of us don't. And really |
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| 106:13 | is the circle will, as you see here that it's a structure that |
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| 106:18 | for connection between the posterior and the halves of the brain. OK. |
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| 106:25 | here between, what was this, is this one called? Do you |
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| 106:33 | anterior and what's it, what's it providing blood to cerebrum? So it's |
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| 106:41 | . So here's anterior cerebral, there's cerebral, they come together form anterior |
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| 106:46 | . But between the two, you'll a little tiny branch between the two |
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| 106:53 | cerebral. So basically, if you one up, you have a way |
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| 106:57 | get blood around it, this is the communicating artery. So anterior communicating |
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| 107:03 | and it's between the two branches of anterior cerebral before they come together. |
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| 107:09 | The last one here is the Basler you can see here's the Basler, |
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| 107:14 | the inferior crotts and what do we in between them? We have the |
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| 107:19 | communicating and all that together creates a . So blood can circulate between any |
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| 107:26 | those points, whether you're on the side or the posterior side. And |
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| 107:31 | , the last thing just to reiterate Basler artery here arises from the two |
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| 107:38 | arteries as they come and join All right. So circle Willis has |
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| 107:44 | anterior posterior, communicating arteries that connect , the posterior, the anterior hals |
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| 107:54 | . I got two minutes. There go. So that's your anatomy for |
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| 107:59 | day. Questions. Yes, you're die. No, no, |
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| 108:06 | So again, if you've never heard before, I'm just gonna say evolution |
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| 108:13 | ac student, right? It just things, some things work, some |
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| 108:18 | don't. So right now, the of Willis is in the midst of |
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| 108:22 | things and it doesn't seem to cause and it doesn't seem to cause any |
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| 108:26 | of major benefit or maybe there's a benefit. And so that's why it's |
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| 108:30 | of persisted over time. But if don't have it, it doesn't seem |
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| 108:35 | kill people off. So kind of . Right. That's, I think |
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| 108:40 | a good way to think about It's truly ac student. It's just |
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| 108:43 | stuff. Maybe this will work. it won't, I don't know. |
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| 108:49 | . All right. You guys, have a great day. It is |
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| 108:52 | . That means we are one day from the weekend. Uh, |
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| 108:57 | I don't know. Uh-huh, it's be. |
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