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BIOL 2301 Human Anatomy & Physiology I - 2301_lecture15_1018
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00:05 Alright. So we are here today talk or finish up with muscles.
00:10 gonna talk a little bit about how is used in muscles or how it's
00:14 up and some of the strategies then we're gonna do is we're gonna switch
00:19 a little bit. Talk about smooth , look at the differences between
00:23 smooth muscle. And then we're gonna back to muscle and deal with some
00:27 um just some broader features of muscles a macro scale. Alright, So
00:33 we left on thursday, we were about how muscles contract. We talked
00:37 all the little steps along the So you should know those steps,
00:40 know, basically say this happens and happens and this happens. And kind
00:44 paint that picture. All right. we said in that process that A
00:48 . P. Is using A P. Is used to break the
00:51 between thick filaments and thin filaments. ? And so you can imagine and
00:56 and that also energy is used to pump calcium back into psycho plasm in
01:02 . So the body needs a whole of energy. Alright. The muscles
01:06 need bunches and bunches of energy to them to do the job that they
01:10 . All right. And so you imagine inside that muscle there are limited
01:15 of energy in the form of a . So, whenever you see the
01:18 a teepee, typically you are thinking is energy. Alright, So if
01:24 not a Biology person and you haven't to have that drilled into your brain
01:28 this is just something. It's just of those things, you know,
01:31 T. P. Equals energy. right. And so there's this limited
01:35 of these molecules that account for And so the body or the muscles
01:41 different methods to ensure that A P. Is always available. Because
01:47 A T. P. Disappears, muscles can't do their jobs. And
01:51 cells die. It's a very very thing. So eight ep needs to
01:54 around. All right. So, use these three mechanisms. You're gonna
01:59 uh If you've been in biology long , you've probably heard of these two
02:04 cellular respiration, aerobic cellular respiration. taught you taught that to you in
02:09 grade biology? May not have remembered , but at least they taught
02:12 So, if you've not not taking general biology course or an intro bio
02:16 , these are things you've seen But this one is a little bit
02:19 . We're gonna spend most of our here. We're not gonna learn all
02:22 details there. I don't think it's for nursing school. Alright. Or
02:27 this class, it's just a lot biochemistry. Alright. So, when
02:33 comes to the first two, or first one, the immediate phosphor jin
02:38 or the immediate immediate energy. how do I get energy right
02:41 All right. So, I'm gonna up numbers so that you can visualize
02:45 a little bit better. Alright. first off, let's pretend muscles hold
02:49 their actual sells about 100 80 It's not 100 80. It's just
02:54 easy number. All right. you can imagine if I have 100
02:58 P. I can break those molecules release 100 units of energy. All
03:06 . And so I've got a very amount of energy, but that's the
03:09 place. That's the first part of system. Now, when we're dealing
03:13 energy, we don't require oxygen When dealing with these different mechanisms that we're
03:18 look at be looking at. All . So, what we're saying is
03:23 that this is how I can get quickly uh to allow me to do
03:29 things I'm doing for? Just general contraction. All right. So,
03:35 amount of stored a teepee that you is about 5 to 6 seconds worth
03:38 energy. I want you to picture a moment you're being chased by.
03:42 , I don't know. What do want to be chased by a mountain
03:45 ? Alright. Mountain lions. Alright. Good old cougar. Because
03:49 Cougars. And why not? we could have been bears. Will
03:54 chased by bears or tigers. All . So, you have to run
03:58 . Now let's say your safety is m away. About how long did
04:01 take you to 100 m World record about 10 seconds. All right.
04:09 gonna run out of energy before you to safety with amount of stored
04:12 Yeah. So, we that's not . All right. So, what
04:16 gonna use is we're gonna use another . It's called my cockiness.
04:19 whenever you see that word, remember that's an enzyme myo muscle.
04:23 cockiness means it's a it's a molecule found in muscles and its job is
04:29 break A D. P. Now A D. P. A.
04:33 . P. Is a byproduct of teepee breakdown. So, if you
04:37 over here, A T. When it's broken and releases its
04:41 energy is released when we take off phosphate from a T. P.
04:45 a T. P. A. a denizen. The T stands for
04:49 So that's three and then phosphate. 123 phosphates. So, what I've
04:54 is I've taken one of the phosphates and I'm left with two phosphates.
04:58 , there's the die. So, a denizen di phosphate. And if
05:02 take off that second phosphate, then become a M. P.
05:06 Tennessean mono phosphate. You see how works. And that's what we're doing
05:11 is we're saying, well, I 80 I can do the reverse of
05:15 reaction. So I can make a . P. Plus inorganic phosphate can
05:19 me a T. P. And what I do is I steal one
05:22 the phosphates from one of the D. P. S. And
05:24 it to the other one to give a teepee and that leaves me with
05:27 . Now that's missing two phosphates. in the immediate that's great news because
05:33 gives me another two seconds I'm now know, another 20 m closer to
05:38 escape. But it's still not Alright. So there's another way that
05:43 can actually store up energy in a that actually doubles our pool.
05:48 And again, I'm just making up . So don't think that we have
05:51 molecules of A. T. We have this other molecule called
05:56 Alright. So here's our molecule And what we can do is we
06:01 phosphoric. In other words we can the energy from an A.
06:04 P. So we bring the T. P. We take that
06:08 . Which is it's not the energy . But it represents the energy it's
06:12 in the bond between the phosphate and it's bound to. Alright. And
06:18 it's not that important for you Just so if you just understand whenever
06:21 see a phosphate moving around, I'm moving energy with it. Okay.
06:26 so what I can do is I break that eight Ep release that
06:30 I can take that phosphate and add to creatine. And now what I've
06:34 is I've stored up energy in the molecule as creatine phosphate. And if
06:39 have 100 molecules of creatinine, then I can do is I can make
06:44 creatine phosphates and then I can go and I can make another 180
06:49 So if I have 100 creatine phosphate P. I have an effect 280
06:55 . So what I can do is can first start burning through that a
06:59 and then it's like oh well I energy. So I'm gonna start breaking
07:02 creatine phosphate to make new A. . P. And then I can
07:06 those A. T. P. little bit later. Right, That
07:09 sense. So think of it like you have $100 walking around $100 in
07:15 pocket. Not a good idea. what are you gonna do with that
07:17 bucks deposit and put it in the ? Alright now you go out with
07:23 friends going to the clubs, So what do you do outside the
07:28 ? You go to the A. . M. And you say I
07:30 to spend my 100 bucks. So do I do is I can go
07:34 take that money out and that's what phosphate acts like it acts like an
07:38 bank. Alright, so I first my 1st 100 bucks. Then I
07:42 back to the bank, take up 100 bucks out of the A.
07:45 . M. And now I'm spending other 100 bucks down. Broke.
07:48 right, but look what it it actually gives me a lot of
07:52 is actually more creatine in the cells there is actually A T.
07:57 So I can actually make a lot energy available in the immediate term?
08:04 in other words, as I'm I'm burning through the A.
08:07 P. And it's like oh I'm to run out of a T.
08:09 . Let's go head up. Creatine . Make more 80 P. Very
08:12 quickly. And so you make up teepee and it basically keeps that pool
08:17 for a longer period of time. about 10-15 seconds of energy. You
08:22 it to your safety zone. The isn't gonna eat you. Alright,
08:27 this is what we refer to as phosphor jin system. Because there's not
08:30 lot involved here. There's just a of I mean, there's just two
08:34 that's involved if you include the 80 three enzymes. So there's not all
08:39 lots of steps which is basically I'm a TP to release its energy.
08:44 I'm breaking a TP to give that back to a P. P.
08:49 . A. T. P. I can break it again. Or
08:52 taking the energy from a TPM handing over to creatine creatine phosphate. But
08:58 I need that energy, I break phosphate and I released the energy to
09:02 it back to a T. Or so that then I can break
09:05 T. P. And you're well why do I have to keep
09:07 a Tp? It's because that's the of the energy right there there's no
09:12 step. The other two are these winded pathways that you have to learn
09:20 uh in biology and intro bio. then when you take biochemistry you get
09:24 learn all not only all the individual but all the individual enzymes are
09:30 And basically the difference between these two you start off with a molecule of
09:33 . Right? When you start off the molecule glucose, the first step
09:36 always gonna be like ah this is you're doing is you're taking glucose and
09:39 breaking glucose and turning it into a carbon molecule. And then what we
09:44 from there depends on whether or not is available. If oxygen is available
09:49 then go through a couple of bunch bunch of steps. One that you're
09:53 with or at least heard of is you heard of Krebs cycle or the
09:57 acid cycle. And I'm starting to heads not going T. C.
10:00 . So basically what you're doing is you're breaking down this three carbon molecule
10:06 make other um um energy producing molecules electron carriers. And then those are
10:13 transported over to another system called Well it's called oxidative possible relation where
10:19 taking the electrons adding it to You break oxygen and you make
10:24 And in the process you make a of a T. P. So
10:27 waters around, that's what you're doing you're using what is called aerobic cellular
10:33 and you get a whole bunch of teepee out of this. Um This
10:36 showing you 32 some books say 30 some books say 38. It's basically
10:41 concentrations and we don't bother really remembering one is the correct one.
10:46 so when oxygen is available we make of a. T. P.
10:52 because oxygen serves as a receiver of electrons to allow us to do that
10:57 auction isn't available then the whole thing all mucked up. So instead there's
11:01 bypass right after glycol Asus. And we're gonna do is we're gonna take
11:06 product at the end of glycol Asus we're gonna send it back through a
11:10 system. And what we're gonna do going to convert that three carbon molecule
11:15 lactic acid. And in doing so renewing the molecules that are involved in
11:21 glycol Asus process. So it allows whole process to kind of serve in
11:25 very circular manner. You don't need have oxygen at the end. So
11:29 is an anaerobic process. And in process you do make energy but you
11:32 make a lot of energy make about 80 P. Per glucose molecule.
11:38 this is good enough, right? under the circumstances when there's no oxygen
11:43 least you're making something and that keeps from dying alright it allows the cell
11:48 do a little bit. But it's a big old signal says when I
11:51 seeing lactic acid build up, it's to stop using that muscle. All
11:57 . And you've probably heard it's this not true. But you heard like
11:59 I get cramps and basically build up acid, it's not that's actually not
12:04 . Cramps are independent of the lactic build up. They just happen to
12:08 at the exact same time. so this is where we go to
12:12 a last resort. Typically ourselves want do this over the long term.
12:17 our oxygen coming from, Well we the myoglobin. Remember myoglobin is sitting
12:21 the cell saying you need oxygen. got some for you right here.
12:24 gonna ask the lungs to deliver some in just a second. And
12:28 you know, you're breathing harder and as you exercise or you're using your
12:33 . That's bringing oxygen to the muscles replenish the oxygen supply. But you
12:37 have oxygen stored up there. So is kind of what's going on over
12:40 long term. This is what's going , like right now we need this
12:44 this very second as we're starting to stuff and this is like, oh
12:47 run out of oxygen. We can't don't have any oxygen, what do
12:51 do? Well, and this system kind of run out of stuff.
12:54 this is a system that our body as a last resort. Okay.
13:01 . It's pretty last any morning. was being the cast. So,
13:09 question has to do with some biochemistry we don't want to talk about.
13:13 . Yeah. Plus, I don't the steps. Lactic acid is a
13:22 carbon molecule. It's basically um switching electrons around. Alright, so with
13:29 out of the way, are we with the with the energy systems fast
13:34 quick short term versus long term. what we're doing so for a long
13:38 , what do we need? Do need oxygen or No? Yes.
13:42 . And do we get lots or little A T. P. A
13:46 . See that's that's the key Right. If your intro bio you're
13:50 learn the 10 steps of glycol, the 12 steps of citric acid
13:54 prevent oxidation, oxidation, phosphor blah blah blah blah blah. So
14:00 long term, short term. Keep simple. So, what I wanna
14:03 is I want to shift now and want to talk about smooth muscle.
14:07 right now, some of the stuff you're gonna look and go wait a
14:11 . I don't I don't get All right. But remember the goal
14:14 smooth muscle is to do the same as skeletal muscle which is contract.
14:22 . Skeletal muscles primarily used for Right? We're talking about local
14:27 Smooth muscle is gonna have movement. what we're doing is we're propelling materials
14:32 through the body, Right? That's the only thing it does. Your
14:35 have smooth muscle on them and stuff that as well. Alright, So
14:39 you dilly, Sorry, Dilate or your pupils that smooth muscle.
14:43 But generally speaking, we talk about muscles. You think about the muscle
14:47 lines the hollow organs. So these your blood vessels, your digestive
14:51 You're going to see smooth muscle around pathways the bronchial walls of the
14:57 Um So, you know, we're about like the ureter, all sorts
15:02 fun stuff like that. All Now, if you recall, we
15:08 about muscle, the skeletal muscle. said these cells are fairly long,
15:14 ? Because they merged together and formed big cells because they merged. We
15:20 lots of nuclei, right? And were basically elongate. They were basically
15:26 . So smooth muscles are basically We are very different shapes were spindle
15:32 , so that's kind of a spindle nuclear meeting their individual cells. All
15:37 . And they're very, very Alright. They lack sarcasm ears.
15:41 they don't have that unit of that functional unit instead because of their
15:48 . They still have the same proteins make up those Z disc. But
15:52 range in a very different way. what we have are these structures called
15:56 bodies. All right. And so our little cartoon up here, these
16:01 circles everywhere. Um These represent where dense bodies are. Right? So
16:07 happens is you can imagine with the . Disc remember what we have is
16:11 had a bunch of thin filaments coming the Z. Discs. And for
16:13 dense bodies you have the same You're going to have thin filaments.
16:17 you'll also have some intermediate filaments to sure shape is being maintained. And
16:21 thick filaments are there as well to of being held in place by these
16:27 filaments. So, these lines are the interaction between the thin and the
16:31 filaments. All right now there's a more mayas and than there is in
16:38 uh the uh skeletal muscle. what you end up with is more
16:43 bridges. So that means stronger contractions a result of that ratio. And
16:49 you can see the arrangement you have last work. So, when you
16:52 a contraction, the cell doesn't shrink a skeletal muscle. Like So it's
16:57 like a ham that you wrap in that that cord or whatever.
17:02 So, you can kind of see , look at how this kind of
17:05 all funky shaped, right? So we're doing is we're taking the whole
17:10 and we're not shrinking it this way shrinking it in every direction. These
17:17 muscles are connected to each other by junctions. Now, what are mechanical
17:23 ? These would be like the Dismas and so on. Right? So
17:28 they're doing is when one cell contracts pulling all the cells around it.
17:32 then that cell is also contracting pulling all around it and so on and
17:36 on. So typically what you're gonna is you're gonna see these cells arranged
17:42 bunches called census Shia. Alright. . She um a singular sensation is
17:48 . So basically you're going to see arranged in such a way that you
17:51 a whole bunch of cells arranged in sheet. And so when you get
17:55 contraction, the whole sheet contracts in direction. There are also sometimes gonna
18:02 electrical junctions between cells. And if an electrical junction between the cell,
18:06 means if I stimulate one cell to the materials that cause that cell to
18:11 . What do you think? What you think the contracting ion is what
18:15 a contraction do you think? What called? What what caused it?
18:18 skeletal muscle calcium. All right. do you think it is in smooth
18:22 calcium? What do you think it's cardiac muscle calcium? Right. So
18:27 , it's like, okay, it's be the same ion. But it's
18:30 to be doing it a little bit . But what you're doing is if
18:34 cell is contracting, that means calcium going into that cell and if it's
18:38 electrically, that means the cell next it is receiving the calcium that's going
18:42 that first cell which is gonna cause second sell two contract, which is
18:46 cause that third cell to contract and on and so on down the
18:49 And so typically what you're gonna see these is that they're going to work
18:56 in in that sheet. All right they do have a Sarka plasma
19:02 Um It's well defined. It sequesters calcium, but instead of it being
19:07 with the T. Two bill of there are none. Instead, what
19:10 have these little indentations called calvi Alright. And it's there where the
19:15 is closely associated with the surface of cell. And so when you get
19:19 actual potential that's going to cause um channel to open up, it'll be
19:24 calcium channel, then calcium floods out the cell. So, again,
19:28 particularly different than what we've already learned terms of calcium. It's just
19:33 It's just kind of different missing T . So, that's our supplies particular
19:37 close to the surface. So, already mentioned it in these hollow organs
19:42 and sensation. And typically what you're see is you're gonna see two
19:46 All right. And so you can here there's the thickness of the sheets
19:49 fairly thick in this particular case. the two sheets, if it's around
19:52 hollow organ. You can think that a pipe right? And so the
19:57 has to uh directions it moved. can move in this direction towards you
20:03 . That's longitudinal. So, I have a longitudinal muscle. And I'm
20:08 gonna have a muscle that's gonna go the circumference, that would be some
20:13 . So in most cases this is you're gonna see when you look at
20:17 vessels. When you look at digestive , When you look at the any
20:20 where you can see some of you find these two layers typically speaking.
20:25 right now, there is some cases you have a third layer. And
20:28 , if I have a layer that's this way to layer, that's going
20:30 way, which way do you think next layer is gonna be? You're
20:35 up and down. That's I was know. All right. It's gonna
20:40 oblique, it goes this direction. , So I can squeeze this
20:45 I can squeeze this way, but I can also squeeze this way and
20:50 a ring of the muscle. Your stomach has that ladies your uterus
20:57 that layer. All right, this kind of shows you that.
21:03 , you can imagine this is the , right? It would go around
21:08 direction and this is coming out towards . Alright. And in terms of
21:13 the two muscles do, you can of the tube? And this is
21:16 make a lot of sense when we into a and p. two.
21:19 when I contract the longitudinal muscle that the structure, just get shorter kind
21:26 like a worm, you see those out in the spring time out on
21:30 sidewalk there all sad. And they're to move. What they do is
21:33 way they move. They have these types of muscles. They get themselves
21:37 and then that basically brings the back and they hold out and then they
21:41 the front end forward and then they again and then they do that.
21:46 that's the longitudinal muscle. So that's of the ways that you move stuff
21:49 you make your your tubes shorter. the other way you move stuff is
21:54 squeeze the tube like a tube of tube of toothpaste. Right? So
22:01 , relax, squeeze, relax. that's what those two muscles are.
22:07 what are these movements that you're gonna movement of blood flow materials along the
22:14 and urinary pathways, resistance to airflow respiration, respiration. Anyone here struggle
22:21 asthma. Yeah, that's when you're muscles are not playing nice. So
22:28 they're doing there's there's constricting and they're air flow through. Alright, lastly
22:34 relaxation. The uterus is a good would be labor is an example where
22:38 see that doing that. Alright, this is where most of you guys
22:42 gonna panic. Don't panic. This easy mode. All right. When
22:46 talked about the skeletal muscle, we an action potential. The potential cause
22:50 opening of channels the channels when they ? Cause calcium to go into the
22:54 . Right? And when calcium went the cell it bound to a
22:59 What was that molecule bound to start ? The T. In with an
23:03 . Which is kind of scary because two of them. So, troponin
23:07 ? And it moved the trump another to allow access to medicine to work
23:11 when acting on Madison interactive to my head begin to contract as a result
23:16 its 80 ps. Alright. So that ring a bell for everybody right
23:21 ? All right. And you got contraction? All right. So,
23:25 have a series of molecular interactions that taking place inside the cell smooth
23:31 We have a series of molecular The differences is that they're different
23:35 calcium still comes in the cells. you can see right there we're getting
23:38 traditional calcium comes into the cell. from the interstitial fluid as well as
23:44 the circle Plaza in particular. That's . What the calcium does now
23:49 it doesn't bind the troponin. There no troponin instead what it does,
23:52 binds to a molecule called cal module it's kind of a nice easy name
23:58 remember cal from calcium module. From in the I. N. At
24:03 end of any molecule is usually refers a protein. So it's a calcium
24:08 protein. That's where it got its . And what can modulate does it's
24:12 defector molecule. Its job is to turn on other molecules and in this
24:17 pathway it turns on a molecule called light chain keenness. Alright. And
24:23 way it turns it on is that takes the energy from a teepee and
24:27 I'm going to add you or really I'm gonna cause you to become phosphor
24:32 . And that's what it does That's what the penis does. So
24:36 can modulate activates the myosin light chain . So, myosin light chain keenness
24:45 you what that molecule is activating the light chain. Alright, so when
24:51 learn when we talk about skeletons. we said we got this head that
24:55 this this long portion is the heavy . The little portion over here that
25:00 this that's called the light chain. so if I have a myosin light
25:06 kindness, what do you think it's the little tiny head? All
25:12 And so that's what does remember we the to the weird thing like
25:16 And so, what it does is son like when it becomes activated by
25:20 module in it starts foss for letting head and it starts doing what the
25:26 muscle did on its own. It those breaking of the bonds so that
25:32 can get those contractions. Okay, it's just different molecules. It's just
25:38 doing the same thing that you've already ? All right. And so that
25:42 going on until you remove what How I get a muscle to stop
25:49 remove the calcium. So how do remove the calcium? Okay, good
25:57 . Since then. Have you heard she said? Yeah, it's
26:01 No, that's why I'd like you to be able to say it out
26:04 . Alright. So when I had skeletal muscle, the muscle is contracted
26:09 response to and action potential. And stopped contracting. When what? When
26:18 were no action potentials. Okay, smooth muscles are the same way.
26:24 I remove the action potentials, I'm going to get a contraction, but
26:29 have pumps in place that are constantly calcium. If I'm moving calcium back
26:35 the cytoplasmic particular um I can't get contraction. That was true in skeletal
26:41 . That's true here. That's the thing that we're gonna see. So
26:46 process calcium ultimately results in the contraction the movement of those heads in the
26:52 that we're doing it though is we're moving troponin and causing trouble minds to
26:58 out of the way. Instead, activating the system that causes the false
27:01 to make and break the bonds here regard to the smooth muscle contraction.
27:10 I remove calcium, I'm no longer cal module and if I'm no longer
27:14 cal module in I'm no longer activating minus and light chain kindness if I'm
27:19 activating minus and light chain kindness? another molecule that comes around and just
27:24 off the phosphates. So they no interact. And so the muscles stop
27:28 this, they just sit or the that. So when you're looking at
27:37 at the molecular level, every place turning something on something is turning it
27:43 . All right. So as long there's no action potentials, calcium doesn't
27:46 in and the whole process is stopped lasted no longer activates. All
27:56 So, I know some of you are sitting there going, this is
27:59 and it's scary. And uh it's two steps skeletal muscle had how
28:05 steps? Just I'll take 3.2 Three steps. Something like that.
28:12 , it's just different names, but the same type of activity.
28:17 there's some interesting things about smooth We're coming on that part of the
28:21 where we get to eat all the , right? That's that's I look
28:25 to. It's like how much food I get into my body? And
28:29 given moment is like part of my goal. And you can tell some
28:36 , Alright, first off, one the neat things about smooth muscle,
28:41 has what is called a stress relaxation . And what this does is that
28:45 the pressure inside that vessel, where structure becomes too great, the muscle
28:51 relaxes. So think about that that that you really love. What's your
28:58 food? Right? I mean like will not stop eating it like a
29:02 of Doritos, like family size bag Doritos. You know what I'm talking
29:06 ? Like oh I'll just have a of chips. The next thing you
29:08 , it's like how do you throw bag? Well, your stomach went
29:13 the process of the stress relaxation That first chip. No big
29:17 Second chip. No big deal. you get through that 1st 16 ounces
29:21 chips, it's like, okay, keep it coming because I've got room
29:25 here. Alright, if you're thinking thanksgiving, what do you do?
29:28 can button that pants and it just gives you that or you wear the
29:32 pants and it really gives you that . All right. Second thing that's
29:36 of interesting about smooth muscle. Remember we said about skeletal muscle? There's
29:39 a perfect length. If you stretch too much. It doesn't it doesn't
29:42 a lot of efficiency. If you it together, it doesn't have it
29:46 have good efficiency. So there's a tone for skeletal muscle. Well,
29:51 muscles, you can stretch it out it still remains as efficient as it
29:57 at that most efficient length. Same when you compress it. All
30:02 because of the way that it's It allows for that to happen.
30:08 characteristic is kind of interesting. We're learn about how muscles get bigger skeletal
30:12 , how they get bigger, When we work out and exercise.
30:16 know that they get bigger. smooth muscle. There are specific
30:23 particularly in the uterus, that are of undergoing division to make more
30:29 Right? So that's not normal for muscle. Alright, basically the muscle
30:36 have now is a muscle you're gonna pretty much forever. And so your
30:40 is derived not in the number of cells that you have, it's in
30:43 size of the cells that you And so here, with smooth
30:48 you can't really increase the size of the cell itself. So what you
30:52 is you increase the number of And so, um we'll just have
30:56 little bit of fun with this. make a fist look at me and
30:59 your fist. You suck. that fist, that's about the size
31:02 the uterus. Okay, now, you think about a newborn baby and
31:07 placenta and how big a uterus Now, It's about the size of
31:11 basketballs. Okay, so that occurs the course of nine months, Going
31:17 about that size to like that. right. Maybe a little bit
31:22 Maybe a small soft, a large or a small volleyball. How's
31:27 All right, but that size shrinks to about the size of your fist
31:32 in about two weeks. So, hyper plastic growth as your uterus gets
31:37 , ladies, during pregnancy. And it regresses back to its original
31:42 Um after pregnancy. So, smooth can be hyper plastic. There we
31:53 . Alright. In terms of when we talked about skeletal muscle,
31:58 said skeletal muscles exists as motor And so in essence, what you
32:02 is you have a motor neuron and directly innovates at the neuro muscular junction
32:06 that particular cell and it causes that two contract here, smooth muscles are
32:13 the control of the autonomic nervous which was gonna be like the very
32:16 thing we're going to learn about this . So, if you don't know
32:19 that is, it's basically the system regulates all the things that you don't
32:24 direct control of like your heart the your respiratory rate, all that
32:30 you can't increase or decrease that just thinking about it, right? It's
32:34 , I can't make my heart go . All right. So this autonomic
32:39 instead serves kind of like a instead creating neuromuscular junctions. Instead, it
32:44 of acts like a sprinkler system. basically lays over the cells and so
32:49 acting on the individual cell, but the census to itself, and it
32:53 its neurotransmitter. And that neurotransmitters just of scattered or spread over the
32:59 And so you get diffusion of the . And so the cells that that
33:04 that neurotransmitter gonna cause that contraction, is then gonna spread to the rest
33:08 the census. You all right. , we have a very different sort
33:13 mechanism were not directly telling the cell to do. We're basically telling all
33:17 cells what to do. And then other thing is that sometimes smooth muscle
33:23 even need to be innovated to tell when to contract. It actually has
33:27 it its own pacemaker activity. some cells are constantly going through this
33:33 of near contraction and relaxation, but contraction basically your action potentials, you're
33:39 getting them. But then what happens you hit that threshold, you'll get
33:42 series of contractions because of its own pacemaker activity independent of what the nervous
33:49 is telling it what to do. , they can act on their
33:56 Now, there's two ways that they kind of arranged and this is not
34:01 what I just said. So, first is called the multi unit.
34:04 can see here there's gonna be something a neuro muscular junction. It's not
34:08 actual neuro muscular, but it's very it. And so, what you're
34:12 have is that the the neuron comes and it's going to have the synapses
34:18 the individual cells. All right, still releasing kind of like a
34:23 But now I'm directing my sprinkler at very specific cell. Okay, So
34:28 basically each of those individual cells are on their own. They're not talking
34:34 the other cells. They are responding . Alright. So where we're going
34:39 see these? We'll see like for , in large blood vessels will see
34:43 in small airways of the lungs. that means you can kind of balance
34:48 The not good the amount of air you're breathing in versus how much is
34:54 into the bloodstream. You can kind balance it in in different areas to
34:58 sure everything is equal liberated. All . Um Your hair follicles. This
35:02 a real simple one. Have you gotten goose bumps on one side of
35:05 body and not on the other And you're wondering what the heck's going
35:08 ? Right. It's like why are freaked out over here and you're
35:11 Right? That's because of this type innovation right there. It's not You're
35:17 all the hair on your body is hooked up to the same system.
35:20 individually hooked up. Alright? Eyes your limbs and your iris is a
35:25 cool one. Um You can it's a reflex. You can cover one
35:30 up and shine light into the other of this. I this I will
35:35 this. I won't right that it's to the stimuli of the light.
35:40 these are all examples of what is multi unit smooth muscle. The individual
35:45 are acting independently of each other in to whatever stimuli that they're receiving.
35:52 else in your body is other than is basically the single units. And
35:56 when you see the word single think in terms of all the cells
35:59 acting together as a unit. So really does kind of have those,
36:04 varicoceles these you don't have individual interaction the it's that sprinkler system of hears
36:10 neurotransmitter, one cell responds in that . When it contracts all that calcium
36:15 in it goes to the next cell goes the next cell which goes to
36:18 next cell which causes the whole structure contract as a whole. These are
36:24 the ones that are self excitable meaning produce their own action potentials independent of
36:29 nervous nervous system um bring themselves really to threshold if necessary. And cause
36:36 contractions. Alright typically though when you self excitable that means only a couple
36:41 cells are and they're the ones that serving as the pacemaker of the rest
36:45 that census she um So here we we act as a single unit?
36:52 the name. I think that's really about smooth muscles. So what I
36:57 to do here is just try to that nice little contrast. You
37:00 It's like here always what we learned skeletal muscle. This is how slightly
37:04 and smooth muscle. See how we of did that. So it's kind
37:07 an easy way if you think smooth behave similar to skeletal muscles but they
37:12 so differently. I think that's kind an easy way to kind of remember
37:16 . So if you know what's going you can kind of just make oh
37:19 they're different. This is how they're structurally or functionally. This is how
37:24 function differently. But they result in same thing which is a contraction.
37:32 right. Are we okay so No. Do we have questions?
37:43 silent. I think maybe I should sit in the middle and and lecture
37:47 there. What do you guys Yeah. Makes them uncomfortable. Makes
37:52 uncomfortable when you sit next time when talk about stuff, you know
37:57 All right. Let's deal with back skeletal muscle. So we're now going
38:03 that bigger picture. What's muscles? are muscles doing? What are some
38:06 these terms? Now if you're taking lab you're going to learn the names
38:11 the muscles and what they do. . It's too hard to do that
38:15 a lecture where I'm just sitting there at a picture and going, oh
38:18 this muscle here. Is that Here's this muscle. It's a waste
38:20 our time and it really is a of your time. All right,
38:24 I'm gonna leave that to the lab so we're going to deal with some
38:27 things that will help you understand the muscles. Alright? So remember muscles
38:33 there to cause the movement of Alright. And there's two different sorts
38:39 attachments we have what is called the one is called the insertion. So
38:44 origin is typically the muscles proximal attachment what does approximate mean closer near
38:52 So when we say approximately we're referring the center of the body so approximate
38:57 closer to the center of the Alright. So here you can see
39:01 regard to the bicep, here is origin. It's closer to the
39:05 The insertion on the other hand is one that's furthest away typically.
39:11 so it's distantly located. So origin . The origin is what is really
39:18 you're using stationary end of the So what you're doing is you're pulling
39:24 insertion towards the origin. Alright, this is the mobile. Typically this
39:32 the flesh attachment. So what you're is you don't have a lot of
39:36 . Um Typically you'll have a lot tendon on the insertion side. And
39:42 what you're doing is you're pulling on and that tendon is pulling on the
39:49 and that's causing the bone to move the insertion side towards the origin
39:55 So here we're distributing force and we focusing the force to cause the
40:01 Alright, so that's the way you origin is I'm pulling towards origin insertion
40:05 what I'm pulling and focusing that force . Now this is terminology and actually
40:12 had one of my upper level students I never realized that's what this
40:16 Alright. Typically you'll hear the term and antagonist and agonist is simply the
40:23 that we're focusing on that's causing the to move. All right,
40:28 it's the muscle that's moving All And so, for example, if
40:32 am moving my arm up like this my bicep Alright, This is the
40:38 we're focusing on and causing the That's the agonist. The antagonist is
40:42 opposing muscle. It's the muscle that want that movement to occur.
40:47 And so here would be the antagonist I'm contracting. Now, if I'm
40:54 my arm down, this muscle no is the agonist, it's now the
41:01 . It's opposing the movement. This becomes the agonist, right?
41:06 when you see the term agonist and , it's telling you you're where you're
41:10 you're focusing on in terms of the of movement you're looking at. All
41:14 ? So, it's a it's a term. All right. Now,
41:19 I contract the agonist, what I'm do is I'm gonna relax the antagonist
41:24 vice versa. If I contract the , you know, I'm relaxing the
41:31 . So they work opposite one So, this is what is referred
41:37 as reciprocal inhibition because if they're both or relaxing at the same time,
41:42 wouldn't get movement. Alright. I'm both most of the same time,
41:46 be stuck. So it's basically contracting relaxing the other, there's a heavy
41:56 over here, I'll use this one right? So when I picked this
42:00 up and you can see this is this is a heavier chair than last
42:03 . Alright so you're gonna get to me hurt myself. All right?
42:08 I have to be careful cause I do have a bad shoulder here.
42:11 , so when I picked this what sort of movement am I
42:15 What am I trying to do when curl this? It's a contraction
42:20 right. And I'm just trying to it upwards like so but I can't
42:25 that unless I have other muscles that me. Where are the other muscles
42:28 are helping me do that do you ? Oh that's bicep is actually causing
42:32 contraction. I gotta put it down . But where else? All through
42:39 back? Right. For those of guys who like to work out,
42:43 got the kettlebells and done the this the swings right? Ever done dips
42:50 fun things. These are called core exercises because you're not just working one
42:55 , they're working hundreds of muscles. all the muscles that allow you to
43:02 your body while you're creating that movement referred to as synergistic muscles. They're
43:08 involved in the actual movement basically They're involved in stabilizing the body so
43:13 the movement can occur. Alright, this is trying to show you here
43:17 like look I'm doing that contraction of bicep. And so what's gonna happen
43:22 in order to ensure that my upper is stabilized. I'm gonna use my
43:26 Boyd to stabilize my shoulder. Just an example. So there are two
43:37 types of contractions isotonic and isometric. gonna deal with isometric. Well I'll
43:43 with isotonic first because you're more familiar that one. Alright. Isotonic basically
43:48 look whenever I contract a muscle that amount of work that I'm doing in
43:54 muscle stays constant while the muscle Alright. So for example if I
44:02 this little tiny itsy bitsy three ounce the amount of work that my muscle
44:07 to do will stay constant, Because the weight of the object doesn't
44:12 . So to overcome the load, force that I have to produce remains
44:19 same. So I am contracting the and the muscle gets taller.
44:27 Did the muscle get smaller from here here? Yeah. Okay. So
44:32 changes in shape when object back Does the weight of the object
44:39 No but does my muscle change It gets length? It lengthens.
44:46 . So what we have here is isotonic contraction. And isotonic contraction is
44:51 the load stays the same. So the force that I'm producing stays
44:56 same. But the shape of the changes when the muscle shortens. That
45:04 contraction is called a concentric contraction. the muscle is lengthening then that is
45:11 an e centric. So when you're curls you're doing isotonic contractions concentric and
45:20 . Concentric and eccentric. The muscle doing the work is still the bicep
45:25 when I put them and lift up easier chair. Right? When I
45:30 this chair up I had to create force to actually lift up the
45:33 Right? That chair didn't change its . And when I'm putting it down
45:39 muscle is changing in shape. I'm putting it down so I'm not just
45:46 . Right? It's don't be Alright, I'm putting it down so
45:52 is control in the bicep. It's east century isometric. On the other
45:58 , is when I increase the force the muscles producing, but the muscle
46:03 doesn't change shape. All right, that sounds kind of weird. All
46:08 . Picture this wall. If I up against this wall, can I
46:12 the wall move? No, I you guys had a little more confidence
46:17 me. But yeah, it's not happen. So I can push up
46:21 this so there's not a lot of . Alright, so I'm not putting
46:25 lot of force in there. My not changing shape but I can start
46:28 more and more force. And my not changing its shape even though I'm
46:34 more and more force now. If want to experience this you can push
46:37 against the wall but there's an easy to do this right? Get in
46:42 put your hands like this in front you. All right now push against
46:47 . You can do it lightly at , Right? Not a lot of
46:50 of force. But you can keep more and more and more force your
46:54 not changing shape. That's an isometric . Alright, so the tension
47:03 But the shape of the muscle does . And here's just a visualization of
47:09 is here. You can see the the isotonic where you have three kg
47:14 muscle contract moves, moves the Here. I'm putting force in but
47:19 not enough to move the weight. , so there's isometric contraction. So
47:25 so means the same metric means Same length. I So, same
47:33 is referring to the uh force that producing. So same force versus same
47:44 . Now mussels have these four plus . Your book says five. My
47:50 slide set four. So I just plus one. So, there's five
47:54 . First off, muscles are I'll. What that means is that
47:57 forcibly shortened when stimulated? All So, your muscles don't naturally get
48:01 when you can when you create a stimulation, they're supposed to get
48:05 Alright. They're excitable. Alright. means that they can respond to a
48:10 and that's what causes them to create contraction. They're extensible. Alright,
48:16 you can stretch a lot greater than resting length. What is You know
48:22 you stretch? What are you Like if I just I'm stretching the
48:26 so beyond its natural resting length. elastic. What that means is once
48:32 stretch them, they're not stuck They bounce back to their original
48:37 All right? So they recoil and they're plastic and this is the most
48:44 thing for our knowledge, not for class, but just that means as
48:48 as I use them, they'll become at what they do. All
48:52 In other words, if you're weak now and you want to be
48:56 you can work it out and you make that muscle stronger. Okay?
49:02 if you need more endurance, you work it out, you can work
49:06 muscle and it will have more So they're not stuck in the state
49:12 they're in their plastic. So one the characteristics of our skeletal muscles takes
49:24 of these. It goes through what called a stretch shortening cycle. And
49:30 a stretch shortening cycle does, it us to produce more force than if
49:36 just had a simple contraction. All . And it's a mechanism that's not
49:41 to visualize or demonstrate, but I you to think about walking quickly or
49:48 . So when you walk or run I apologize because no one's gonna be
49:51 to see me always want to stand something, but I know if I
49:54 I'm gonna hurt myself, I'm old . Alright, So when you walk
50:01 run, when you when you step , you basically point your toe to
50:07 body right? And in doing so you're gonna do is you're gonna stretch
50:10 calf right? So everyone take you where you are, just point your
50:15 towards. Can you feel it? you feel that stretch in your
50:18 Alright. So what you've done now you've gone through an eccentric phase.
50:23 extending the muscle and stretching it further it normally wants to be. Now
50:29 already said this is not particularly helpful terms of creating strength in the
50:35 but what we're doing is we're it's like stretching a rubber band,
50:39 adding energy to a system and creating energy. We put our heel
50:44 What's going to happen is that muscle to contract. So basically it's like
50:49 the the rubber band to go back its original shape. But what we're
50:53 do is we're gonna quickly revert that stretch into a contraction. And so
50:59 energy that was stored up in the now gets used as a as as
51:05 to push off your toes. It allows you to go through that last
51:11 which is a concentric phase. And this is creates greater force and it
51:17 propels you forward. So this is that this this stretch shortening cycle is
51:23 counter or a preparatory movement to allow muscles to do more work than they
51:30 would do if they just went through contraction. So typically we see these
51:35 we're trying to change velocity. Typically see them in the legs um primarily
51:41 of the way that our legs are but it helps us to propel ourselves
51:44 . We don't see it quite up the upper body. So a stretch
51:48 cycle isn't just a contraction, it's stretch that quickly reverts to a contraction
51:54 create more force. Another physiological relationship we need to understand is force versus
52:08 . And I tried to make this . So remember we talked about concentric
52:11 eccentric. Alright, when we're talking concentric reaction or concentric contraction here,
52:18 and velocity are inversely related. All , so that means the greater the
52:23 , the less the speed and the the force. The greater the
52:29 the faster it is. Alright, or heavy. Right. Light or
52:46 . Heavy. Ready? How fast I go with something? I'm not
52:51 a lot of force. How fast I go in terms of curls?
52:58 , so not a lot of force quite a bit of speed. I'll
53:09 not to So can I go fast this? No. So you can
53:20 that. Just think if I'm lifting if I'm lifting up something big,
53:25 go slow. Right. When something light, I could go fast.
53:30 that's concentric. Alright, East centric the opposite. There's a direct
53:36 All right. Now if I'm putting down. Right. If I go
53:44 I can hurt myself. Right. . You can imagine I'm putting it
53:47 the table, right? So if going boom, I have very little
53:51 . It's just very, very Alright, So instead the less force
53:57 I'm going to produce, I'm trying slow down the movement of the muscle
54:01 that I have greater control over So the less force that I
54:04 the slower the contraction, right? it's an e centric. So I'm
54:09 it's going slowly here in the opposite . I'm going fast. I'm creating
54:16 much contraction as I can to slow the way that the muscle relaxes are
54:22 relaxes because this is s centric. ? So here, you know,
54:27 got to produce a lot of so I'm producing quite a bit of
54:31 to ensure that this is taking its . Okay, does that make
54:37 It's hard to do when I'm trying lift stuff up. So the idea
54:40 is if I am if this is going this way, that's not a
54:43 . But if I'm fast going that , I can cause damage to the
54:47 itself, so I'm slowing down the that's taking place so that the muscle
54:54 like so here, you know, takes a lot of effort to come
54:59 , but coming down if I just , I could damage the muscle.
55:03 the contraction is very, very fast ensure that I'm releasing energy slowly,
55:09 makes sense. All right, so e centric and constantly knows we're just
55:15 on the bicep. So in the the antagonist muscle you can expect the
55:19 would be occurring right now. Your are designed to create specific movements,
55:33 specific movements. Alright. And so arrangement of the muscle versus the tendon
55:39 going to direct the direction in which muscle is going to create that
55:45 We have pin eight muscles and non eight. Alright, so pennant muscles
55:51 what we have is you can think the tendon. The muscle fibers themselves
55:55 gonna be attached obliquely to that So I'm gonna use here the unit
56:01 , pennant are the easiest ones to it. So here's your tendon going
56:05 up through the middle. But look how we're attached to that tendon.
56:09 here to the side. Here's this right here, look at how we're
56:13 just to the side. So when muscle fibers contract, which direction are
56:18 pulling the muscle? Are we going direction or are we going this direction
56:23 we going another direction? Are we this way? Are we going that
56:28 ? If I'm if I'm connected to side like the union, what do
56:32 think? Yes. Alright. You know logically if I have a rope
56:38 I'm pointing from the side of the , the rope is gonna follow
56:41 All right. And so you're doing same thing. The muscles are doing
56:45 same thing here, they're going in direction in which they are arranged.
56:50 so what these do is they don't a lot of force along the length
56:54 the tendon. Instead. What they is they produce greater force to cause
56:59 muscles to move slowly. All so you're gonna see movement along the
57:06 of the of the fibers and that is pulling in the direction in
57:11 And so what's happening is I'm creating force and that tendon kind of pulls
57:16 direction like. So. Alright, pin eight is gonna be slightly different
57:23 the non pin eight. So here's perfect example of the pen eight or
57:28 pen eight. Non pen eight. pin eight. And here the fibers
57:31 parallel. It's like being at the of the rope. If I pull
57:35 the end of the rope, it's follow me. Right? So if
57:38 pull this direction, the tendon is that direction, that's gonna make the
57:41 move that way. So here we're get high velocities, right? I'm
57:47 this direction. The muscles gonna move way I can it goes that
57:50 But if I'm pulling off to the , I'm not getting pulled that
57:54 I'm getting pulled kind of to the like. So, so I'm creating
57:58 strengths, not high velocity. So can see their arrangements there's a very
58:06 types of arrangements for inmates. So more that you're going up to the
58:13 , greater force, greater speed. have more going off the side,
58:19 force, greater speed. Alright No force. Alright guys ever played
58:25 of war? Okay, you get person at the end. They're the
58:32 that are directing the rope backwards. ? But what you're trying to do
58:37 you're getting people lined up on the and they're trying to pull this
58:41 But really they're actually pulling opposite. are almost at an angle. So
58:46 get a lot of people at different and their combined work is basically
58:50 Now that kind of makes sense. wish we could have a rope in
58:56 . We can play tug of war be awesome, huh? The whole
59:02 . Yeah, we could just divide up and see you guys versus you
59:09 . I see him looking around the going, hey, I can beat
59:14 . So, the idea here is way that muscles are directed in that
59:19 and how they're attached to the tendon whether the muscle is there for strength
59:23 velocity. That's the easier way to about if it's a pin eight,
59:27 dealing with strength if it's non pin , you're dealing with velocity. All
59:33 . And they have different sorts of . But all you gotta do is
59:35 gotta look at where the tendon is ask how is that fiber connected to
59:39 tendon. Is it up to the or is it directly in front of
59:44 behind? And that will give you sense of what you're doing now?
59:51 to make your life easier. About muscles in the body. Uh probably
59:58 the lab I think learn like maybe of them. It's not all of
60:03 . I guarantee it's not all of . You'd be like, no,
60:06 not doing this anymore. Law definitely the direction I'm going.
60:11 here's the secret. It's gonna be in the nervous system. Everything in
60:16 body is named in a very simple so that you can understand what it
60:21 that you're looking at. All They're just using a language we no
60:27 speak on a regular basis. Latin. And some greek. All
60:33 . So muscles are going to be based on location or position or structure
60:38 size or shape or origin or insertion its action. Right. So there's
60:45 lot of yours in there. But if you look at the name
60:50 you're sitting, I have no idea this is. Just stop for a
60:54 . Take that step back and then , okay, is it being named
60:57 shape is being named for its Is it being named for all these
61:01 things? And that will help So I just pulled parts of names
61:06 . So rectus. What does that you? There's a lot of muscle
61:09 erectus. What does that look like ? So when you see something erect
61:15 direction is it? Going straight up down. All right. That makes
61:20 life easy doesn't it? Okay. even sounds like bad latin. Like
61:25 made up a word rectus. size bravas. What does that sound
61:35 brief? So small again looks like latin, longest. Right? I
61:43 does it sound like someone just made a word? It's long, so
61:47 must be longer. Right? Major miner. There you go, vast
61:55 . Another one. Very very You see so all of a sudden
61:59 if you see something and it's like little tiny muscle and one of the
62:02 vast us. Do you think it's be vast us? No it's like
62:06 right I can eliminate some of these shapes of the muscles. Bell
62:10 What shape is that? Come Yeah. Triangle. Alright rhombus.
62:19 it's like a rhombus. You guys the rhombus is got that drill in
62:22 has two parallel sides. Okay Yeah quadrilateral has four sides to
62:31 Alright. Like a quadrilateral. And then actions remember we went through
62:36 the joints and you know movements. ? So abductor pulls up Abductor depressor
62:46 er arguing these words like hard now like oh right flexor versus extensive
62:56 Sounds like someone left off a letter right and left, the opponents creates
63:05 opposing movement. Alright so when you're these names don't let the big scary
63:13 scare you, you already know just what some of these words mean,
63:21 , this is gonna be true in nervous system as well. Very often
63:24 see these things that are like these words and they're like like big $10
63:30 and it's like oh what they've done is they've just said, here's the
63:33 point, here's the ending point, it. Yeah, that's it.
63:41 right. Now the point of the muscles is to move bones.
63:48 And so what we're dealing with here basically a lever system. Alright,
63:53 bones are serving as the levers, joints are full crumbs within that
63:59 And then the muscles are the things are applying the forces to create
64:04 Alright, so we're basically talking about . Arms or moment arms,
64:08 So what we have, we have applied force applied force is the thing
64:13 causing the thing to move. So you had a rock on the
64:17 what you do is you say I to move that rock, it's big
64:19 I can't move it. So what gonna do is I'm gonna take a
64:21 old stick, I'm gonna jam it the rock and put another rock underneath
64:24 stick and I'm gonna apply force to the rock. So pushing down would
64:30 the applied force, the resistance force be the rock and then the thing
64:36 I put underneath the stick, that's fulcrum and then the portions of that
64:41 on either side of that fulcrum. are the moment arms. And so
64:45 have a moment arm for the resistant . You have a moment arm for
64:48 applied force. So your muscles are same way. That's kind of what
64:53 doing is we're trying to create an , what is called a mechanical advantage
64:57 move a structure. I think it Archimedes, I don't know for sure
65:03 you know, I wasn't well Um but I think he said if
65:06 give me a fulcrum long enough I move the entire earth. And that's
65:10 , mathematically, that's true. All , because it's a force multiplier is
65:16 a lever is. And so our is designed around this, this this
65:21 of of bones, joints and There are three basic kinds of levers
65:26 we have all three of these in body, but two of them are
65:31 commonly than the other one. So least common is the first class lever
65:35 hear what you have in first class is kind of what we just saw
65:39 . So basically you have you have force that you're trying to move.
65:42 there's a resistance force, that's Purple fulcrum is the green and the
65:46 forces. The red arrow, So you can see that's kind of
65:49 we think of a lever. This kind of the system we have we
65:52 of. And this is one of least common in the body. All
65:56 . And an easy one to think is just me nodding my head
65:59 So if this is the force that trying to move, the applied force
66:03 be the muscle on the back of neck to cause my head to move
66:08 the axis. Alright, that would a first class lever. Second class
66:14 is kind of like you see here the wheelbarrow. But what I've done
66:17 I put my focus on the edge putting the force trying to move in
66:21 center and I'm using my applied force the opposite side. So the full
66:25 , the applied force are on the and the and the resistant forces in
66:28 middle. All right. And so example that you'll see almost everywhere as
66:32 wheelbarrow, it's easy for me to materials if I put that focus on
66:36 front end and I left on the side and I can move stuff around
66:39 opposed to be carrying stuff directly. that type of lever, the second
66:43 lever still not that common. And example that they have here is me
66:48 on my tiptoes here using the muscles gastronomy asse in the in the
66:53 right? It's basically attached at my . Alright. My full crumb are
67:00 are the balls of my feet. so weight is or the resistant forces
67:05 body. And so when I'm lifting up on my toes, that would
67:08 an example of a second class Most common is the 3rd class
67:14 Alright, this is again, shovel would be an example of this.
67:19 here are resistant forces way, way at the end. Our fulcrum is
67:24 the other end and the applied forces the middle. Alright, so you
67:28 see here here is my uh my force, here's my fulcrum, my
67:36 force. I'm basically pulling up here cause this to move and this is
67:43 most common type. All right, when you're asked third class levers are
67:52 what most of the muscles are. you just look at where's my
67:55 Where what's the thing I'm trying to ? This weight down here is in
68:00 of my of this arm. So am I applying the force? It's
68:04 in the center. I'm pulling on to move this upward, I moved
68:16 slide, it just shifted up So if you're using on the
68:19 I'm just I moved one up. thought this slide would be better than
68:22 one. That's right, that's the one, all right now in your
68:28 , let me back up. So getting that time of year. Um
68:35 meat, people. White meat dark meat. White meat. We
68:42 start a war here. Dark White meat. Alright. When you
68:47 at a chicken or a turkey, can see the white meat. White
68:51 is primarily breast meat, Right? dark meat is primarily thighs and
68:57 All right. Yeah. You're made of white meat and dark meat differences
69:03 you do not have it in one . Your white meat and dark meat
69:07 mixed together. And you can see in this picture there's your white and
69:10 dark meat. All right. when you look at a muscle,
69:13 have both white and dark meat. . Really, what we have here
69:17 different muscles. That's red muscle versus muscle. That's white and dark
69:20 And we basically name it based on types. Type one versus type
69:24 So type one muscle is very, slow. It's the smallest muscle that
69:31 have and has very little or it lots and lots of myoglobin. Hence
69:34 it's red. The type two muscles broken down into two types. There's
69:39 that's reddish and there's one that's white it's reddish. It means it's gonna
69:44 my assassin in or sorry, not scene. Myoglobin in it. All
69:47 . It's just has less. You kind of see the difference here.
69:50 is lots of myoglobin. Myoglobin. , So, the type two,
69:56 are going to be slightly different. don't they're not particularly slow. They're
70:01 kind of fast. Alright. And they're gonna do is they're going to
70:06 glycol assists to do their job. other words they're not gonna go through
70:11 fast. Um The I mean the term energy you said you're gonna use
70:16 term energy. Alright. The type be very little myoglobin. So they
70:23 have no oxygen in them. They to have the oxygen delivered to
70:27 They don't store it up real So they burn through their A.
70:30 . P. Very very quickly. these are the ones that produced the
70:34 and most powerful contraction. They're the ones and those are the ones that
70:38 most prevalent in your body. So little chart which is that first slide
70:42 she said kind of shows us down basically we can do a comparison in
70:46 of fibers. What do they Well we can look at how fast
70:49 they twitch, remember what a It's a contraction we can't see.
70:53 . So we're asking the question, quickly do they contract? So type
70:57 slow. Type twos are fast. . That means because they're slow.
71:03 develop force over time and then they over time. Whereas here they quickly
71:09 their force and then they quickly relax terms of power development very limited in
71:15 force. Type two's produce force very quickly. So they basically have a
71:20 of force and they do it very fast and they relax very quickly and
71:24 in terms of fatigue. What are doing with Type ones very very
71:28 They're resistant to fatigue. They're resistant fatigue because they have lots of oxygen
71:32 them and they take their sweet So they never burn through their
71:35 T. P. Very quickly. so they have a high capacity for
71:39 activity. Type 2s. They're very inefficient. They fatigue very quickly.
71:45 very low aerobic activity or capacity. what does this all mean? Well
71:55 other way that you can look at is you can talk about in terms
71:58 sort of energy source they have, type ones are referred to as oxidative
72:04 means that they're using their oxygen. they go through the process of oxidative
72:07 relation. And so they're using T. P. So they fatigued
72:11 very slowly and they produce a lot a TP to do their job.
72:15 the other types they're referred to as like elliptic, meaning that because there's
72:19 oxygen, they just go through glycol . They stopped there and they basically
72:23 up that lactic acid to producing a that they need. Alright, so
72:28 very very fatigue A ble and most us basically have an equal concentration of
72:35 fast and slow. Type one versus two. But we may lean one
72:41 or the other and that leaning also different sort of athletic abilities. And
72:47 this kind of path this chart right ? You kind of look at and
72:50 all right, am I good at ? Do I like to run long
72:54 ? Do I tend to like to a lot and I can do that
72:58 I'm skilled at it, you in other words, I don't get
73:01 . If that's true, then you have more of these fast twitch fibers
73:06 you do the slow twitch. All . Whereas if you're a sprinter,
73:13 have more of the uh backwards. , that's backwards. They mark these
73:23 things wrong, This should be fast if you're a sprinter basically produce fast
73:31 . So the idea is, I can burn through energy very quickly
73:35 cover short distances very quickly. what's interesting, we've talked about
73:42 so I don't think we need to that. What's interesting is how our
73:47 muscles get bigger and bigger. Now is conceptual stuff. So I don't
73:52 how I ask questions on this, it's usually like which ones uh,
73:56 know, go through massive hypertrophy and ones don't. So, I really
74:02 this picture because I think this is the Jamaican um track team is the
74:09 the two things, but we had different runners. This guy on the
74:13 versus the guy on the right, guy on the left, what type
74:14 running does he doing? Do you endurance and this one on the right
74:19 and you can see here that the actually has a high degree of
74:26 right is not just in his it's throughout his entire body,
74:30 And so the reason for this is of the different types of muscles that
74:34 involved in this. So both of are incredibly good athletes, right?
74:41 guy looks like he just, you , came out of africa starving to
74:45 , and they just kind of put track suit on him. But you
74:48 know that he's in incredibly good right? I can't do what he
74:52 without a question. This guy looks he's been working out his entire
74:56 right? And so this has to with how our muscles are developed and
75:02 in response to the exercises that we . So, when you have type
75:07 muscle fibers, what you're gonna do you're gonna have a great deal of
75:13 . In other words, they look because they create that massive force to
75:18 that fast twitch. The endurance on the other hand, don't have
75:24 sort of same type of hypertrophy what they're doing, they're built for
75:30 . And so what you'll see is see in a person with Type one
75:35 that the muscles don't get large, they do have a high degree of
75:41 that our interview or our vascular rising the tissue. And so they're able
75:45 get all the auction they need to and replenish all right? So
75:50 you're going to see very few And so the muscle fatigue is
75:53 very quickly, but you get a of power enforced and it's not just
75:58 the legs in terms of the it's everywhere. This shows you a
76:02 bit better. Alright, so here got to you guys before and the
76:07 . Alright, this actually when I this picture, I thought it was
76:09 college roommate, he still looks the way, but look, this guy
76:13 here is probably has more type two type one and this one has probably
76:17 type one and type two, they both went through training of some
76:22 and what you see, this one has all that muscle tone that we
76:27 attribute to being stronger and faster. one, he's still stronger than he
76:33 previously, but he still has that frame to him. And what I
76:38 to point out here is that different of training give rise to different types
76:43 muscles that we're that we're going to out. But depending on what type
76:49 muscle types you have a greater affinity , or your body has, you're
76:54 to work those muscles out and you're going to increase the number of
76:59 So in other words, if they're doing the same times, actually going
77:04 and doing this high resistance training, not going to look the same because
77:10 one doesn't have the same type of , He's primarily type one. So
77:14 never going to have that same sort physique, you can't really switch muscle
77:18 between Type one and type two you're , you're born with. If you
77:22 , if you're a sprinter, you're going to be able to be as
77:26 as an endurance runner as someone who more Type one muscle, we can
77:31 you and teach you to do stuff you'll never be as good as because
77:34 have the wrong type of muscles. , if you're an endurance runner,
77:38 never be a sprinter because you have different types of muscles. And so
77:42 different types of activities that we're going do in order to become better at
77:48 growing that particular muscle. So if want to become stronger right, the
77:55 of muscle that you want to do your type of work that you're going
77:57 do is gonna be resistance and sprint . So what this is gonna do
78:01 it's going to increase the cytoplasmic cytoplasmic density to get the word right?
78:07 basically it increases the number of interactions thick and thin filaments and creates more
78:11 them. And so as a result muscle which is tiny, gets bigger
78:15 bigger and bigger, you increase the of muscles you're making the muscles bigger
78:19 . They hypertrophy. This enhances also calcium release, which produces more
78:25 And then the other thing that it is that it also allows you to
78:28 fatigue a little bit just a little when you're doing with aerobic endurance.
78:34 you're doing is you're strengthening the type muscles. Alright. So what this
78:38 it increases the aerobic capacity. What means is and these two things are
78:42 but they're slightly different. It means you can perform at the same absolute
78:46 with less effort, meaning if I'm a mile it doesn't take as much
78:50 for me to run run a Alternatively, I can also run the
78:53 distance faster as an example here. are going to increase the size of
78:59 taipan muscles But because they don't have same degree of hypertrophy as the type
79:05 , you're not gonna see it quite well. But what they do is
79:09 also increase their their resistance to fatigue . Right? So basically you provide
79:15 with more fuel and more blood vessels so you basically have greater endurance.
79:21 , what happens if you're sitting around a couch potato atrophy? Alright,
79:29 as a result of working out and if you don't use it, you
79:33 it. All right. And this a really good example here. This
79:36 was in a cast when you're in cast, basically the cast is doing
79:39 work as you're moving around. You see here here's the muscle that she
79:44 had. I think it's a She at the leg here. That muscle
79:48 worn down. Alright, basically don't it. It's gonna break down.
79:52 right. It's that atrophy is a in tone, size and power.
79:58 is reversible, but you can make irreversible once the cells die, they're
80:04 replaceable. So this is one of conditions where it's like, oh,
80:09 gonna just keep moving around, moving , moving around. So as long
80:12 you move a background, your muscles work as much as they need to
80:15 order to maintain their activity. Everything we're doing from here on out nervous
80:23 . Yeah, I know. See on thursday. You're
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