Transcript for:
Myology overview

we really start taking notes on 111 where do you guys classify muscle tissue it's one of the four what yes analyzer are made but more based in her four principal tissues correct and on day one when we went over those four principal tissues we essentially said muscle tissue is a specialized tissue that shortly some contracts now what are you guys heard about muscle tissue Benilde it shortens and contracts anything it can tear you can damage it right if you get muscle tears loss of strings lots of blood deep red cover what else happened in fact we said shortens in kinetics and you can't stretch one slope into muscle tissue but muscle tissue you know the self can't stretch itself so that's a really good question so it's not a connective tissue but it will be associated with connective tissues and one of the things that I also like to talk about with you guys is how many heard phrase muscle fibers dad what does that was any means you guys the muscle fibers yeah I like that too a little of the vigilance so muscle fibers you guys if you look at an actual muscle but you guys'll have the opportunity to do you can see little strands of football like look like fibers strings and those are technically muscle cells muscle cells and muscle fibers are really the same thing and I actually do not love them they call muscle cells muscle fibers because there's actually a smaller structure than a muscle cell that literally translates to muscle fiber we'll get there but for the most part you guys when people say muscle cells muscle fibers a lot of the times they're kind of using interchangeably and it's so cells that have this ability to shorten to track I'm just giving you guys a discussion where and plenty of places to take notes but I want to just make sure that you guys also have this idea to make a whole muscle are you guys okay with this concept it's gotta be made up of thousands and thousands of muscle cells or muscle fibers so you guys see a muscle in the cadaver that when you look at a picture of a muscle all the little stringy things you're seeing are the muscle fibers to make up a whole biceps muscle it's thousands of cool now what we didn't talk about a day one and this is pretty cool there's actually three types of muscle tissue and you're going to see them on this first page and the first one is called non striated muscle or non stranded smooth muscle nobody comes along trying to muscle they all just refer to it as smooth muscle and I'll just plain of striation thing in a second you guys but this is your cartoon drawing and what we're gonna say it is smooth muscle is we're going to get just simple points on all these smooth muscle is small spindle like cells you can kind of see those little spindles equal spindle like so small spindle like cells and where do you find it totals are gonna be we're gonna see those Australian in the second oh I'll show you those know you'll see those for sure but uh cardiac the heart it's their organs you find them in your organs you guys you guys what does that really mean sure really so your organs give me an organ that you might think have smooth muscle uh hard cuz that's gonna be carve out your guts how do you guys drive your guts do it muscle let me give you guys an idea in here anything that's essentially made out of tube in your of a tube in your body for the most part it's got smooth muscle on think of the tubes before you guys write all this down esophagus is it to your colon is a tube what about your veins your blood vessels are tubes with smooth muscle on them your bronchial tree which is like your trachea bronchi tubes smooth muscle your your which carries your pee from your kidneys to your bladder smooth muscle on it it's a tube the uterine tube a uterus large smooth muscle the new body actually all have smooth muscle in there wall and so it's a tube you can bet that it's likely got smooth muscle in it but for right now you guys you could say essentially it is things like your organs if you want to give yourself examples most typical ones are like the jest of tracked blood vessels respiratory tubes anybody I've asked on here the imitators never got an asthma attack will have the smooth muscle in the ground bronchial tree will sometimes spasm and close often that's part of the reason people will get an asthma attack now Peter all I can hailers that people take that is a bronchodilator it relaxes the smooth muscle and that too so it's kind of cool so a couple of other things that we want to know about smooth muscle you guys is that when they were looking at this type of muscle tissue they were looking at smooth they were looking at cardiac and they're looking at skeleton they all looks different on the microscope they also figured out that they were hooked up differently to the nervous system and they found out that some of the muscle tissue was what we would call under voluntary control and some of it was other involuntary control what do you think's smooth muscle what type of control it's involuntary controls they want to know voluntary believe it or not you guys are hurting the muscle before anybody remember when we mentioned it the first Penn goosebumps the erector pili muscle was between muscle Australia too but so in other words you guys do you have to think about when that oreo cookie is in the depths of your jejunum which is your small intestine and think about doing some little wiggly dance and move it around the corner to get it through the digestive tract no I grew up with three sisters I can definitely tell you they have very very descriptive words in verbage about how the uterus was not under voluntary control so and being a whole class of women I'm sure you guys can relate to that Wow it is not under involved under voluntary is very involuntary very natural cramps even labor things like that so pretty crazy last factoid on smooth muscle the cells can divide the cells can divide yeah so in other words this cell could undergo mitosis and make a copy of itself that cell can make a copy of itself so which is pretty remarkable when you think about the size change of the uterus during pregnancy either literally gets bigger and part of the reason it gets bigger as the cells copy themselves to literally make the actual house speakers well there's kind of a hostel we call the cocoon of life drink okay so the next one is called striated cardiac muscle now based on this name you guys where are we going to find it higher the heart and if you guys remember what I mentioned about the smooth muscle I said those were short spindle looking cells these are longer branching cells you can see like this cell in particular gets long branches across here like it sounds like literally a boy here who wrenches makes that sound effect - so what do you think how's it looked up to the nervous system voluntary or involuntary involuntary good you tell the story every single time we have this lecture had plenty of people are in fact not a lot actually just a few for like course it's in a creepy voice and I say like okay make your heart beat at 72 beats per minute per minute now go can they do it no we know that if you go running down the hall what should your heart rate do it should go up if you rest and kind of meditate breathe deeply it should go down but that's like using the same logic of I'm going to control my jejunum or my gut muscles by swallowing the cookie no you know it's gonna work on its own right you got your heart rate to go up by controlling your voluntary muscles that we're gonna mention in a minute so do you have any questions on cardiac muscle that's a great question and they cannot cells can divide cannot divide which is a really clinically relevant question you guys because if you are in theory to kill a smooth muscle cell could you replace it yes because that's how can if you are to kill a cardiac muscle cell no why is that so detrimental we do need it absolutely right and what's a really common illness that kills cardiac question yeah heart attack you guys you cut off the blood supply to the heart you literally kill cardiac muscle cells and if we could divide them we would have no motivation to eat healthy ever as far so I'm gonna call you up on the weekend your buddy coming up our Jack when we regenerate cardiac muscle cells and I'll be back to normal yeah doesn't happen that way right so those muscles I've seen it in today overlaps like literally where somebody's had a heart attack or that a nice fan of muscle tissue is I've seen a band just collagen and scar tissue from heart attack arts it's pretty crazy to think about so it gets replaced by a tissue that collagen can contract with the skill like these cool cells literally do this and shorten contract to help pump propel blow so moving on to the next one striated skeletal muscle now you guys I'm going to really go nuts on quizzing you on what striation means but I'm going to tell you because that's why I was here so this is a actual stain of skeletal muscle tissue and it looks striped which is what striations essentially mean but again most people just refer to the three muscle tissues and smooth cardiac and skeletal now skeletal muscle tissue you guys longest non largest and longest cells do not range longest and largest cells do not British you know I don't totally down as far as like if that gives more because they're not more powerful than skeletal muscle cells and I'm not sure what functional something I'll see if I can find it look into it and find a bunch not totally sure if there's the significance of the branching is but it definitely was a structural feature that you could biopsy and see and see a difference between the two cells now one of the other things that we want to mention is wherever you find it what do you guys think of muscle tissue this is when she think of you look at that picture over there that's all skeletal muscle tissue so it's all the muscles on the skeleton yeah so just almost guillotine essentially all the muscles you guys massage all the time all the other tissues you so voluntary or involuntary voluntary you guys can choose snap tenure you move these whenever you want so they're the voluntary control last thing I will mention is the cells cannot divide why are you surprised so that is interesting you think okay a lot of people think like how do you get stronger right but how do they get bigger if they don't dividing their honey muscles get bigger factors and I can start tissue would be actually not functional tissue because collagen can't contract and you're right these muscles are we beat the crap out of these you guys and they just come back for more pretty awesome so if you want to become Arnold Schwarzenegger because you guys have all seen somebody build and you know the pale if the cells aren't defining how does the whole muscle in and of itself get bigger essentially all that happens you guys is these are all individual cells right when you stimulate muscle growth the cells you have just get bigger each individual cell they call hypertrophy when a cells simply gets bigger they just this time they're going to test questions but that's essentially the work she do something in the gym stimulate them and to make them bigger if you actually have to create more structural proteins inside those are they're so exciting and you're gonna see how that gets stronger and literally they can bigger but you have to eat protein to do it so you guys hear about protein gives any questions on those yeah yeah that's right illustration is refers to strokes and and it's when they would skim them when they looked under the microscope so this picture right here then let's go this is striped kind of like a zebra you know and so the smooth muscle doesn't have that type of an appearance it's stained underneath the microscope alright let's turn to page function of muscle tissue what we briefed on these you guys just because I think you guys already knew this functional muscle tissue is definitely to facilitate movie you guys can see that at the top of the page correct now I could argue that you would be moving anything it could be any other three muscle tissues if it's skeletal muscle tissue is going to move my skeleton if it's cardiac muscle tissue it's going to move love yeah we moved our beloved if it's smooth muscle tissue including food it could be moving urine it could be moving all sorts of different different things so you guys want to write all that I think you guys kind of generally understand this stuff contracts and it's going to move something whether it's bone a substance in a tube or even blood correct I think that's contracts and move stuff but I think you guys would logically good okay than skeletons in with my skeleton if it's cardiac it's gonna help facilitate moving blood if it's urine it's a Yerger to move urine if it's the gesture track is gonna food stuff like that now the next one support maintain posture is probably going to be more specific to one of the three so do you guys say skeletal yeah skills and health support maintain posture all of them can definitely produce heat that happens and you guys get cold you shivered what happens when you go to the gym you sweat like crazy because guess what they produce a lot of heat yeah skeletal muscles spell skeletal muscles especially that's what you sweat so much so all of them who technically will produce heat it's just in unison when you talk about just the sheer like surface area of all the skeletal muscles on this picture you guys can see over there and an intensive exercise activity both majority that heat comes from those guys yeah definitely technically anything that burns ATP so any cell will produce some level of heat but nothing like skeletal muscles not necessarily well that's more than the joint of you know itself what keeps you from overheating some sweat glands a Highland Carlo just reduces friction in the axe you know know that the heat that these guys produces mostly gonna be cooled by sweat yeah so how many of you guys have ever heard of fast twitch slow twitch muscle fibers in your entire life well guess what we're going to talk basics of them so let me show you guys we do this skit every other anyway so here's the deal you guys that's the most we all know in love we call the biceps it's a pretty familiar with that just this view here if you guys were to take a biopsy of that literally take a tissue sample look at them in the microscope when you see what looks try and look different than cardiac you know but different than smooth and one of the other things you'd actually be able to see is that not all of the muscle fibers or cells excuse me together are exactly the same they've actually see some that are a little bit smaller in diameter and some that are a little bit larger manner and they've actually classified them into slow twitch and fast twitch if you guys look to this chart at the bottom of the page do you see where it says differences in cell structure if you've got a slow oxidative type one you guys just right next to that just slow twitch slow oxidative type one slow twitch and then you go to fast glycolytic type 2b and you just put fast rip so that's one little far right not the middle name far right don't worry as much about correct yeah so you guys see where it says slow oxidative type long it is just go through this with me I'll tell you what's more important to focus on in a minute but just kind of read through the system that worry too much about notes right now so the slow oxidative type line are referred to as slow twitch muscle fibers so again every single muscle in the human body you guys has a percentage of both like if you guys looked at my biceps you might see like 6040 you're not coping on a percentages because it depends on a muscle also depends on the person so some people might have more fast twitch muscle fibers and their calf muscle then slow twitch compared to their friend or something like that ok so but regardless in general both muscles will happen every muscle will have a percentage of both so the slow twitch them they have a great blood supply where it says mini color fiber red because there's tons of blood vessels and that's why fiber diameter small iron mention that intensity of contraction low speed of contraction slow kind of makes sense because they are slow twitch glycogen content is low mitochondria they have a lot which means they could probably produce a lot of ATP because normal a lot of connery produce 36 and that Krebs cycle we talked about and the resistance to fatigue is high so what are we getting at here you guys each fiber type well let me compare that before you declare cut print go all the way to the other side to compare and contrast here fast glycolytic not so much for blood supply fiber colors white because they don't have quite as much blood fiber diameter though is big so that means that their intensity of contraction is going to be high speed of contractions fast glycogen spend is high mitochondria is what though few so that means they might have to run off of glycolysis which produced only two ATP per glucose right and then their resistance to fatigue look at that well so what you guys are getting here is we're getting to kind of extremes here you've almost got these slow twitch muscle fibers that are great at endurance but they don't contract very forcefully and they're not very big or powerful that make sense and then you've got these other muscle fibers that are really powerful really forceful can get really large in size compared ly but do they last forever no essential yeah and you guys for example issues will get your quads you guys have all of this with your quad muscles and if we took a biopsy on all of your guys's quad muscles you would have both you'd have some fast twitch and some slow and you'd see some difference like you might have been 250 you might have fifty five forty five and it just depends on the person and in general for women tend to have more slow twitch than fast as opposed to min and then there are a higher percentage of fast versus slow and so for example playing basketball they used to do a lot of guys who they used to do a lot of jogging and running long distance running back in the old school training protocols and when people started figuring them out they're like this is stupid why are we doing this why would somebody who started figuring out at and physiology seems stupid to do long distance run or basketball players yeah they're their Court is 94 feet in the NBA four feet enough in the end they do explosive jumping sprinting that means they have to have some level of cardiovascular endurance absolutely but nowhere near say like 10k runner or even a soccer club now soccer players will have four versus be two but there's a difference there right and so literally you guys no matter who you are you can kind of train which muscle fibers you want to focus on so if you went to the gym and you started doing really really really heavy lifting which muscle fibers do you think you going to fast because they're the powerful and they once a movement if you didn't high reps like three sets of twenty which five or you need to get into a slow approach and if you go running marathons you're going to get into more of slow twitch versus if you started to do something like Usain Bolt those which is sprinting so if you are just your average person who's not trying to with the goal beat and you can't dictate which ones you have per se you can just deal with one zero or do you do that so if we took a biopsy you might be sixty forty two it's mostly on there what I call the weekend warrior athletes it's mostly non preference what do they like to do do you like to run do you like to play basketball and so just main actually based on what their preferences they tend to focus training on more because if you like running long visit Russia naturally train your slope which if you like basketball or football or or like something explosive in actually train fast which it's there's no changing now there is a little of those middle groups that we're not going to talk about in that middle row those can move from one end to the other a little bit they can modify but the two extremes in our image converter change those so what I want you guys are kind of just focus on in general for the slow-twitch the biggest key is that they contract more slowly do they have greater endurance prep more slowly less forcefully more slowly less forcefully have greater endurance he's not yeah contract more slowly less forcefully and having more endurance you don't strike but have more endurance just because that's kind of a pro right less forcefully okay yeah more slowly let's forcibly have more endurance how would you guys describe a fast which quickly yeah less no yeah quicker forceful but less innards [Music] like I'm curious to know but it should seem very yeah yeah my general thing is I have a hard time putting an absolute on the king of all diets yeah so it's just because of but I beat you even though you're positive science not me don't I know yeah no let's move again so so ladies and ladies here's what we're doing 30 turn page and I'm going to show you guys muscle bellies and tendons now key points on that even hopefully just wasn't stuck you guys drove them and we're gonna do a little bit detail fast twitch with slow twitch but just those key points that you guys have written down there important for our class now skeletal muscles we're going to take a look at here or anything is the basic enamel of all skeletal muscles essentially have and you're gonna see in your notes sir there's a muscle belly and tendons okay so let's start the muscle belly the muscle belly is the red meaty contractile portion the red meaty contractile portion essentially everything highlighted in red here that is the muscle belly the red needy contract so do you guys see that the muscle belly is essentially what the part that's made up of all the muscle cells all the muscle fibers that is the muscle belly that red media contract out for you that will actually shorten so every muscle that we're going to talk about the skeletal muscle will have a muscle belly they'll come in all sorts of different shapes and sizes though the other component that we need to know about this though is attended the tendons attaches the muscle belly to the bone taxes the muscle belly to the bone and that's what's highlighted up in the elbow up here you guys tendons will come in all sorts of Link's shapes and sizes as well but they're gonna have that same overall function is that they attached muscle belly to bone yep yeah so this one's got technically three tables on this muscle do muscles it when you die yeah rigor mortis and hurt around 24 hours and then what happens is myosin and actin break down and just a bit mental axes because all calcium runs in moves TTC out of the way depending I guess but the thing about the next section you guys this is going to be the most exciting thing for you next time we're gonna do muscles next term you're going to learn these things called origins and insertions and they're glorious and lots of fun so we get to give you as an introduction to what these mean so if you go down below you're gonna see task insights you're gonna see two words origin versus insertion let me give you guys the textbook definitions and then we'll kind of discuss make sense them the origin where it says extend you guys is the less mobile attachment is the less mobile attachment okay now if the origin is the less mobile attachment probably means the inserting is what the more mobile attachment okay so kind of step back here you guys we got an origin insertion we just talked about the differences there but what's the word you wrote for both of those attachment so both of them are attachment sites for the tendons that's what they have in common both the origin insertion are attachment sites for the tendons but where they differ is one's more mobile and one's less mobile depends on the muscle but you guys what is the definition of a tendon that attaches to the muscle belly to bone right so you're always going to have a tendon associated with its muscle belly that's going to attach it so here's the deal you guys this is a muscle that we're all really familiar with biceps so it's a good example to start with now which part of the whole muscle couple is because technically you guys in our definition the whole muscle includes the muscle belly and it's tendon okay now this the muscle belly is the part that actually does is the shortly yes the tendon does not change shape or regulations they change shape it doesn't shortener contract it doesn't have any muscle cells to do that and it wouldn't make sense to have this thing change its links because what will happen is you guys is the muscle belly contracts so imagine this you guys you know not a very good specimen that you can kind of get an idea here is this is the biceps there's biceps tendon coming down right there this thing contracts the biceps tendon stays the same length though so if the muscle belly shortens from the tendencies symlink the bone has no choice but to come up with it right and that's essentially what happens now here you can see some tendons up here and a tendon down here when we get to next term you guys during like you're going to a page eventually that says biceps brachii and I'll have this picture of the biceps up there you'll have by setting up topping the fine print will say two-headed muscle on the break him and I will say blank space insertion with blank space and it'll say function with a blank space and all we're going to say is what are we looking for with origin we're looking for where it attaches to the skeleton the insertion we're also looking for where it attaches to the skeleton the differences the insertion can move so I want you guys to give me an example here's two attachment sites in here salon boom boom when I contract my biceps I want you guys to tell me if this spot is the origin or in the insertion you ready because I have two spots up here that have a spot down here too why did this attachment site move no do you see that the insertion essentially gets pulled closer to the origin like the origin is kind of its anchor point let's use a different example here's one of your quad muscles attaches here and there on there in one minute one who's gonna be the origin one who's going to be insertion when I contract my quads this one was one surgeon that hasn't moved and this one stay the same fix and so that's what we'll get to in future you guys don't have to memorize any specific origin insertions today we're going to wait until we actually get to muscles and it just tells you where it attaches to the skeleton like right here on the skeleton is called the radial tuberosity so they did the insertion of the biceps it's called the radial tuberosity don't write that down just giving you an example do you guys have any questions on that ok the next page is going to be very very exciting partly because some of you might get obsessed with action here this is one of those pictures you guys that is definitely worth covering in at least two we're labeling however you guys like to to make sure you label or color as clearly as you can just because I promise there will be questions on all the stuff we didn't talk to it that's it you'll probably you questions on origin of certain basic like what's the Morgan it's the fixed one insertion it's the muscle belly partly shorten some contracts tendon so let's take a look at this here and let's introduce you guys to a cross-section what part of the body is this you look about if you only have one and it's a long bone you either have here or you have here because we would have two bones if it was there or there correct so yeah this is actually in cross-section through the bridge and you guys are looking here and this is pulling out three dimensionally the muscles here the trend show this three hip muscles the triceps with biceps and muscle we've learned you the medullary cavity huh yeah excited okay so here's the deal let's do some coloring but let me so what I'll do you guys is let me give you the note and then you can cover so muscle cells specialized cells they can what shortened slash concurrent specialized cells that shortly slash contract and before you color we have a little bit of someone you might try to color individual top so I'm not going to point anybody out here's the thing so this you guys you guys seem like these kind of area and they pull one out so you can see a lot better I would color the one that's pulled out because if you color each individual dot it's impossible to color the space in between that we actually have to color so I would actually just cover the muscle cells out and then we'll just cover one of those little shapes being pulled out right there you should kind of conceptually did but these are your skeletal muscle cells in red that you're covering here and remember to make up a whole muscle you need thousands and thousands of muscle cells I show you guys that video or with the leg where I tried to tug on the connective tissue and Tara did you guys so the day last day was for the last week no I didn't teach you guys last one there to cut like the worst case of strep throat it was nasty like it would not go away yep yeah it's pretty time headed with yours - like blaze Maddox and white abstracted but it's having gonna work any more time as muscle cells you know you're gonna give to colorspace all right so we did the muscle cells you guys now the next thing we're going to color is this stuff called endomysium really important point here and our lysine loose connective tissue that surrounds individual muscle cells so loose connective tissue that surrounds individual muscle cells and when you guys color it you're more than welcome and I would just recommend it just coloring on this one but you guys can see it would be really challenging with your pencils to get a neck and then you can look we're supposed to leave some space gray there color something else in there so that can be challenging inside that's why I keep saying that's just powder this one it just makes it a lot easier so loose connective tissue which is that yellow stuff in there it surrounds individual muscle cells analyzing them yes breakdown in the Lyceum endo means within my means muscle muscle you guys need more time oh yeah Prabhat okay so Paramecium is the next one paralyzed give you guys if the blue stuff but wait to come up let's skip it no that's really important is dense irregular connective tissue that wraps a group of muscle cells so it's irregular connective tissue that wraps a group of muscle cells color in the saving for your Booker campaign but I can't say this is a real big day you guys for your list grows the Maroni said when in doubt call it dense irregular connective tissue you guys now periosteum you have a fibrous membrane that's regular connective tissue there the dermis bit of dense regular connective tissue and you've got this Paramecium then we're an even have two more things to it which we may add now so but I want you guys to kind of start really focusing on this what does it have no meaning what is parent around now we're going to look at this other stuff called epimysium okay yeah so epimysium you guys is this great stuff but let's write the note down dense irregular connective tissue that wraps in individual muscle now what's the key then are you guys whether they not say it said an individual muscle and not same muscle cells anymore we're saying muscle this is creating stuff so I want you guys to think about this for a second while you're coming every single muscle in the human body that you guys have names before in your life has become I seem wrapping around itself so the triceps has its own member my single a biceps quadriceps they have their my steam wrapping around isn't amusing now on that are not correct in that cut inch yep and so make sure you have your coverage they're all that tissue okay so my seem dense irregular connective tissue the Raps muscle now you guys see the bottom part finally down all right betcha everybody he distinctions between all four of these wrappings weird fat she's made of dense irregular connective tissue that wraps a group of muscles hmm subscribe to a group of muscle now I'm gonna zoom out so you guys can see the river engineering zoom back in justly no but essentially it's going all the way around the whole group to wrap a group of muscles if you guys get confused just let me know sometimes it's hard to get lost the lines a little bit here I mean is ooh man anything or you come by just let me know which side [Music] oh the adipose decisions built-in so that yeah so once you get this I'll help you guys how far down is the fashion this is a cross-section what would this layer be right here the very tip-top nervous what would this be dermis here guys this doesn't have that little area that makes it look like the fatty tissue does but then that would be the factor is out yeah okay and this is where you guys really get to start playing the pin game and you push a pin through the human body you start to know layer by layer by layer which it goes through so our future what is this right here well let me just show you guys here so this is the whole thing okay that's a little bright now the the triceps which is a 300 muscle you guys would kind of have the same orientation here this is just kind of like showing you what like individual muscle cells and individual petition graphics would be like by showing you in this one now one of the things that's interesting about this you guys is that we've got four connective tissue wrappings that we just mentioned med surround muscle tissues so I always like to do this you guys just to kind of write it all down here so I know my sinew is ready now this is a just paralyze iam epimysium fat shot couple things I kind of worked out my head as a kid I'm as a kid as a student is that some of these were wrapping cells and some of these were wrapping whole muscles the deeper I got is wrapping cells so these two were actually wrapping cells right of the muscle right but then these two were wrapping whole muscles and I went like this one of those there's like one [Music] endomysium wrapped what what did your dad say one individual cell ranked muscle cell Paramecium wrapped a group of muscle cells epimysium wrapped one whole muscle faster wrapped a group of muscles so as you move out you move you wrap bigger things obviously and think about these is all of these are made out of blood except this one this is the only one that's made of loose connective tissue but all the other ones are made out of dense irregular connective tissue and they're just thinner versions of themselves she is this one's gonna be the thickness because it's the biggest this is gonna be a little thinner think of like a thicker cotton t-shirt versus a thinner cotton t-shirt and a pair of my seams well these two you can actually see with the naked eye it actually seems definite actually you can see these soon they sometimes you can get a feel for this cuba cross-sectional muscle tissue this one not so much now one of those reasons you guys on threads down but one of the reasons it makes sense that the epimysium is made of loose connective tissues because it's wrapping muscle cells and one of muscle cells have to be able to do move to make it a little more loosey-goosey right around the most of cells and also allowance allows blood vessels to get right to those cells and things like that so I'm gonna show you guys a couple of pictures here Ken can erase this so you can see a little better so this is a cross-section this is the thigh though rather than the break-in and you guys can see facture right there if you look that's epidermis dermis hypodermis in that white line it's fashion can you guys see these other white lines right there yeah that's up of my seam starting to separate the quads four muscles there you can see them right there I put my steel lines that are actually separating the muscles into individual muscles because that's what we set up a mighty big which work those februar training so now you guys can't really see Paramecium very well two naked eye you can't see fashion at home I see but if you guys took all those tissues and looked at a little microscope the faction the epimysium the parallaxing periosteum even all the other things you guys learn better made out of dense irregular connective tissue remind me what that looks like an amazing microscope what it did my cracks right in a whole bunch of green collagen fibers going in every which way and we said it's strong in all directions so for your guys's viewing pleasures we take you to break I have this little video for you because it's an interesting concept that I'm gonna have you guys think about while you're gone [Music] you really did a good expression so see you guys this is a dissection and this is the skin removed now what is this white stuff you think that's a faction now the yellow stuff is still seeing the adipose because remember we had epidermis dermis hypodermis then faction okay now you can remove this stuff pretty easily from the fat right and underneath you can see the muscle kind of transparent there now this is the part where if you guys don't want to watch you don't have to but zoomed in there you can see that fashion fashion - yeah okay okay so this is a video that we try to give you guys some context on how strong fashion is here see this section here is official veins show is fashion right here this is dense regular connective tissue [Music] here's something we let the socks down partly because it keeps the hands and feet moist if you guys remember the stratum lucidum really hard to keep the hands of the feet moist in a cadaver lab and so they are the first to dry out so a lot of times to keep the socks on like moisture on from our preservative it keeps them from drying out faster so but yeah that was an example of just how strong that tissues and that's Pacho and so you guys are going to keep one of these in stock are you talking about how can I manipulate this stuff can I stretch it can enough the short answer is this stuff doesn't stretch very much at all think of it like a room like a rope I can't pull apart and so but if you cut it with something sharp you can this and how I actually do it is I actually pull it if this is the FAFSA I generally pull it up from the muscle underneath sniffing with scissors and then I actually gently separate the faster the muscle because what you guys will deal with is mild factual adhesions where you get a little fuzzy stickiness stickiness little fuzzies is so technical but you can get little adhesions between the fash and the muscle tissues and so that's one of those things for massage influence and now you guys know it's not just that on the outside of muscle then you have an another later on the just wrapping an individual muscle then within that whole muscle there's more dense irregular connective to wrapping a bundle of muscle cells would be called Paramecium then around individual muscle cells are some more colleges and things like that as we talked about students massaging and manipulating collagen and connective tissues and just from the power of touch and you don't always know if you're manipulating the FAFSA the epimysium with a pair of mice name or both luckily it seems as though the mechanism seems to be similar to affect both tissues when you guys start feeling things underneath their possible adhesions or binding of the tissue it's sometimes hard to know is it fat sure there's a little deeper with the epimysium I get a sense that as you guys be more experienced you'll probably get a feel for it it feels a little bit deeper more superficial but it's still not easily to totally know in my effect from the FAFSA you might expecting with deeper structures begin like I said the mechanism of affecting those tissues is very similar effectively the same you don't have an x-ray vision to do that but it doesn't matter you're still going to work about it the same way to shoot it's more resistant with more force I haven't heard anything conclusive about that not that I can see I can see it may be getting a little less pliable with age just as all soft tissues and connective tissues tend to do a little bit or a little bit weaker it wouldn't be me I would say any tissue you warm up per se but like I said I used to have teachers of another massage hold of a mommy named that would say stuff like when we put fashion in the oven it melts so when you guys rub it under your hands you melt it when it's 350 degrees in first oh it's not a clear analogy at all and it doesn't it's just like we know like in the emergency department somebody comes in with a crushed injury and their compartment of their calf is swelling up like crazy the fashion just sits there and like good luck and it won't load of stretch and they have to literally do an emergency fasciotomy and cut the fashion open so the muscle can release its pressure so chemical they stitch it back together chilukula so I have to always be clear I talk to people about fashion is not really pliable to stretch very well that doesn't mean the Asajj therapists own affect it it's just I can be clear of like how it's affected versus stretching versus are you helping with the adhesions in the college interactions with the deeper tissue because you guys learn about the human body before you take another class at least my experience was when I was growing up was like you hear things out on the street like ligaments do this tendons do this right basically kind of think about this real quick when we talk about a tendon we said the tendon who connects the muscle belly to the bone correct you look at an actual cadaver here you can see the tendinous portion coming up here continuing from the muscle belly and it actually connects there now when you look at this those completely two different structures is there something that's like looming the attempt attendant on to the muscle belly and there's not actually it's way cooler than that I'm going to show you guys what we end up seeing here in a second is that the collagen fibers that make this tendon essentially these tissues actually continue through the muscle belly and then just emerge on the other side it's essentially that the cells just stop and we're going to kind of show you guys that picture that actually creates this one really really strong complex rather than trying to like literally attach this substance to the muscle belly a substance that could create a lot of problems of that muscular tenderness junctions at the muscular the tennis Junction and instead we have this really cool diagram right here to show you guys kind of what's going behind actually show you what's going on there so first let me just explain the picture and then we'll kind of show you how the tendon attributable to later there's a really basic diagram here and you guys will actually notice that we used the same colors that we did on the previous page just to remind you guys endomysium loose connective tissue that wrapped an individual muscle cell paramecium dense irregular connective tissue that wrapped a group of muscle cells through the muscle cells right then epimysium wrap normal muscles and then faster after group so that was just I just essentially reviewed that last page now this picture has everything from a fashion but it's a different view you guys are essentially looking at a section like that okay the grinning that would be representing what the epimysium okay don't cut anything yeah let me explain it here and then the blue I'm going to zoom in just really is the Paramecium and that's wrapping a group small cell so you see the blue right here you guys and there's a couple of muscle cells in here and then yellow is the endomysium so I want you guys to take a look at this pretty awesome whoops wrong direction do you guys know this the green and the blue ends up from point A to point B and just continues through there and that is essentially how we create a tendon here in second it's pretty awesome the muscle cells essentially just stop and what's left over here here we call the tendon so I'm going to give you guys a couple of notes here to write down in animal color and all of you guys know more simplistically I'm going to color every little detail this picture just the key points so we see structure of the tenon and it's this relation to the muscle belly okay what we're gonna write there is that the epimysium in the Paramecium attached from one bone so I'll write a Democrat will be easier yeah Ephraimites you paralyze you continue through the muscle belly and attached to the next level that's kind of working I know and I'm gonna just say this you guys I know I made that really worried but I counted you to have that but here's the key point with this so right over there the same fan here essentially this is it the tendon is the continuation of the Paramecium and a mousy as by far most important point this is kind of give you the details of kind of to think about it like three dimensional year they structurally how it's literally going all the way through from one end to the other this one is that's what the tendon is it's the continuation of these connective tissue wrappings that we mentioned that attach to the bone computer end how epic is that so what I would do before I read anything else is I would take the same color that you guys used on the previous page for epimysium and don't do what I did it as a student for some reason I try to start in the middle and when it's black and white and your guys's picture it's like I'm getting lost in the lines like you're playing a trick on your eyeballs just start at the end of the bone stay on the outside lining green go there and you like to do two lines for the NYC I'd use the same color that used on the previous page because it keeps it more consistent so that would be the epimysium so you want to label this screen is the it's pretty awesome Bertha Street I know okay now the next part is you guys the para might seem this one we got a color for lines this is I remember trying to begin to play tricks on my animals don't try to go in the middle it start from the four lines that actually attach to the bone on either side and then just trace it through and they can use the same color that you used on the previous page just makes a more consistent but the blue is which color is the para my scene you guys know to read around the red of things are up there correct you want to cover those you guys unless you want to because we're also you're just going to focus on those two things and cutting because we're creating attending here but you would see between all your blue lines you get the muscle cells in the endomysium that's the endomysium so the end up mics even the muscle cells stop and then just a pair of money saving the end of my scene continue so you guys could wave a magic wand and just destroy the muscle bellies at the muscle you can see that connective tissue pattern you made any more time on those blue lines or whatever color you're using play tricks on the racist [Music] okay but it would be multiple muscles so part of it would be covered by the faction but not like the whole so because for example if the biceps just the top part of the biceps would be covered by the fashion on the other side and it just skips over because the bone actually separates the track sets from the bicep so it just wraps around a wider surface of them so the other thing we need to mention you guys assists relation to the bum what happens at the bone is this the epimysium and Paramecium blend with the periosteum make sure you see another periosteum and compact bone so you guys can see just sure you come down some of those fibers you go periosteum these are collagen and bone yes there is is there collagen in periosteum so it's very houston made of dense regular connective tissues so all this is a seamless kind of blending of collagen and this thing's attaching to the the periosteum the deeper compact bone and that's again when it Yanks it pulls the bone it's a pretty awesome again we've said that a lot today but I'm going to continue to say it now before we turn the page do you guys remember what tendons were made out of which is neither dense regular next issue and that is true you guys to make sure on this page you know tendons are made of dense regular connective tissue just somewhere on this page right tendons made of dense regular connective tissue it's regular okay now some of you might be a little upset about that or a question arise your mind and that would be okay because what did we say that the epimysium param IC was made of it's an irregular right and we just now said that the tendon is a continuation of these dense irregular connective tissue structures don't let it fool your beautiful minds you get it don't let it run through the winter you know all that happens is when the periosteum and I'm sorry that the mice and the pair might seem good to hear guess what the collagen fibers should start to do they just start to align themselves and grows so through here the colleges in the dense irregular fashion walls and the muscle belly wrapping it as soon as the cells and all those collagen fibers to align it goes you know I have to write that much detail if you guys still just know the Tenon's made of dense regular you're totally fine I just mentioned that because some students have been like they look at Perry ops compare my team and f1 I assume they like dense irregular connective tissue this stuff becomes the tendon but Jonathan just told me the Tenon's made it's regular so that's why I mention make sense okay so it's turn the page twice we'll do muscle architecture later different days where you start on page 118 we're gonna build up a love story of an epic proportion coming our way now on page 118 you guys are going to go deep into the muscle so we're gonna very very microscopic here and one of the challenges that I experienced as a student is I felt like they didn't just simplify it for me the very beginning and so what I want to do for you guys is really helpful meaning you guys can let me know if this kind of helps later on but 1:18 there's a big gap underneath myofibril once you guys just make this flow list this flow chart for me I'm just oh this step-by-step down and there's a list so keep up here in a little bit all right over here this list I'll keep up the whole time and will reference it but you'll have it to kind of make sense of things so I'm gonna start at the top for us here and I would just write up maybe if you guys just have space here or right there or either side you want to I'm gonna start with a whole muscle okay now you guys know this question how do I make a whole muscle a whole bunch of what yeah I'm gonna say muscle cells okay say I pull into muscle cells okay now the next answered you guys aren't gonna have but don't make sense as we go so would you guys say that muscle cells are a subunit of a whole muscle yeah because they're the subdivision the subunit smaller units to make up a larger unit now to make up a whole a muscle cell I make muscle cells out of these things called myofibrils and again you guys don't know these or teaching just a second but again this flowchart helps us so you guys have been saying a myofibril is a subunit of a muscle cell correct a muscle cell is a subunit of a whole muscle we're literally just building some smaller to bigger here something smaller than a myofibril in other words that you have to make up a myofibril with is a whole bunch of sarcomeres and the sarcomeres you guys know him these only more sense as we go we're going to make up of three main proteins myosin actin and TTC when you're getting these will make more sense as we go but I wanted to get this flowchart for you guys so you can kind of have a smaller a bigger would be from bottom to top so I think tt singing in the future carry on through the old-fashioned that's my flash players okay so here's what we're gonna do your guys's picture is better than the one I have up here I'm gonna explain why so you guys have essentially something similar to this except you guys know this you guys have a whole bunch of tops right there you guys haven't even a full screen pull out of that dot yes almost beyond that you guys have all those dots so I'll use my picture see how those little tiny dots right there and then we pulled one of the dots literally out of there each one of those dots is a myofibril and so another birch you guys I pulled out strung out one myofibril right there are you listening that is a mild fiber this whole thing and therefore every little doc there's a myofibril okay so I just watch the label this string this whole thing as a myofibril its whole thing cuz I pulled out one of the dots yeah because I pulled out one of those dots so you could see it a little bit better yeah it's with me on that okay now you only know what we're going to do for the wildfire realism right now is it just right underneath mile five well underneath that paragraph just right it's a subunit of a muscle cell hence one of the reasons I don't like muscle cells being called muscle fibers because what is a myofibril translate to a muscle fiber which is technically seven unit of a muscle cell is your note for the modifiable okay now the next thing I want to show you guys is I wrap it in so if we keep on to our list we have a myofibril that we've mentioned you guys if you see in here this is the whole muscle cell right that bigger one that's the whole muscle so so you got muscle cells there and then almost in that muscle cells a whole bunch of silence now how do I make up a whole bunch Maya fight was based on my list the sarcomeres right so I use a whole bunch of starters do you guys see where I bracketed the circle here in red there and I'll walk around there as horizontal lines yeah I'll show you I bracketed it in red there that's one sarcomere from there to there yeah there's another one there they're just stacked in tune so that's a sarcomere that's a circle between those horizontal lines so that's a circle mirror and that's a circle mirror just racking up those horizontal lines show you individual sarcomere so you haven't just stack yeah so essentially so just kind of righteous bracket1 hey did you see that okay then okay all right so the sarcomere you guys that kind of it out a little bit word in my opinion on this the sarcomere notes are actually on the other page so I actually prefer to you guys it opens up like this now so starting here on this page kinda looks like there's some piano keys going perpendicular to its length so if you guys come inside that now if I take one of these sarcomeres you guys notice that I said to a walkie there's actually two sarcomere stacked and in there if you guys look at this part right here like this do you guys see that these are there is a sarcomere there's a sarcomere there is a star from there so this is a whole bunch of sarcomeres attached together there so technically like four one two three one three one five so you see what I mean they're pressed so let me give you guys this analogy here so let me give you the note someone will talk about rather than a star come here you guys just do me a favor because we got to get the notes and we'll talk about it sarcomeric is a functional subunit of a myofibril functional subunit of a myofibril this is the thing that those are the contracting of a muscle cell it's the functional subunit of a myofibril is the thing that contracts so to give you guys an idea this is one what that's one sarcomere in the margin of your guys's page where it's tough if you turn it this way you can see the sarcomeres are actually stacked end to end to end and that whole string of sarcomeres creates one all my own five and these things are the things like I said that are the guys that do shortening and contracting the last thing I need you guys just to write down to see up here where it says z-disk in the margin or Z line these started my hair just say that's the attachment of the sweater the sarcomeres attached to each other or to sarcomeres attached yeah Ziva's or to sarcomeres attached we're to sarcomeres attached and if you guys look in your picture you see sarcomeres it kind of going look like this and even look like that see the difference we're gonna see how this actually happens this is the relaxed state we're gonna see that's when your muscle contracts but I'll explain that in more detail in a few minutes we have a couple other players to our above story that we have to talk about but I want you guys to depress percentage because there's a lot of foreign names here conceptually I feel like I'm gathering from you guys you get the whole idea that we're making larger things with smaller things they're just funny names that we kind of have to make sense of I make muscle cells of my firewalls I make my own firewalls or just our clear stuff in and how we stick to the sarcomeres together is a thing called the CD disk and now we're going to just tell you guys what the sarcomeres are made out of and that's all these funny-looking proteins in here that's the myosin the active mttc to do that we have to turn back to the other page okay so I've taught this lecture a few times in the most successful way I've been able to do this you guys are moving awful clumps I don't know why folks just work for people here's inflamed okay whatever so you guys see this whole thing is the circular and the bottom of the page you're going to see this thing called the thick filament this is one whole thick filament and you guys can see that in your picture correct what I want you guys to know is that the whole thick filament is made up of a whole bunch of myosin molecules okay think fulfillment is made up of a whole bunch of myosin molecules then the whole thick filament is made up of a whole bunch of myosin molecules yes molecules can be all sorts of thing molecules can be carbohydrates molecules can be bats molecules can be proteins in this case these are proteins because we're dealing with lots of stuff now the whole Golf Club analogy you guys are paying what is this guy talking about here is a whole thick filament and we set up thick filaments made up a whole bunch of what myosin molecules one myosin molecule you guys is one golf club you guys feel any better to me this looks like a whole bundle of golf clubs just like kind of bundled together you guys give it any with it so if I took out one golf club here I have some shorter golf clubs that were like right there right some longer golf clubs that came out all the way but one whole golf club with the shaft of the golf club and the thing that you'd actually hit the ball with it's one hole myosin molecule so a whole bunch of golf clubs would you mind so you got it and that's kind of what how I use that to make you guys kind of visualize at least try to help visualize what's going on here if I had one myosin molecule it's really only have one golf club in there that make sense yeah now the myosin tail what do you guys think which part of the golf was hoping to read the tail central shaft yeah so the tail is the shaft of the molecule and so I mean that's kind of hard to label because there's a whole bunch of myosin tails in here but I can get to like one myosin tail where right I don't know I'm writing you tiny [Music] it's like an algae shaft okay the myosin head would be the let me give you the before you need to know I'll give you the analogy you have to know this about myosin head this binds let me rephrase this attaches to the binding site of active so just take my word for it so attaches to binding site and we'll get there we're gonna keep building on the story there's a couple of holes it's kind of like one of those movies a very you know intriguing love story or there's some gaps myosin and actin if you must smell that's the only teacher you get they are greatly in love I just actually know that in the company but it is they don't they go golfing together - yes story keeps holding and morphing this years going so you guys have that right attach this to the binding site of actin the heads you guys are ready to actually hit the golf club though like hit the ball that would be like mind some head right there they're actually oriented in three dimensions like you have like little golf clubs in some like this that's so that would be us viewing it from that perspective does that come out and so the ball folks are out like that so this you you guys is that's looking that way so you kind of have all the golf club heads coming out and then the tails will be you kind of in the center there so so you've taken care of mine that's half the love fair here that's going on the thin filament you guys see binding sites for molecular motors we're gonna see active molecules what I want you guys to know is that the thin filament is made up of a whole bunch of actin molecules kind of the same idea with the myosin where we said the mind the thick filaments made up a whole bunch of myosin molecules the thin filament is made up of a whole bunch of molecules okay just okay about that so you guys kind of they're theater so you guys can see from your picture that this is a thin filament right and we said a thin filaments is made of a whole bunch of actin molecules one actin molecule is one little bead you guys that is one actin molecule okay and I kind of think of it almost like you guys had like a string of beads like two strings of beads parallel and you kind of just twist them around each other that's it now we already wrote something like this down with myosin but underneath you guys are going to see molecular binding sites this is where the myosin heads bond or the myosin heads fine okay just about done just about ready to start those stories of course once a long time oh good what stories start with but before we go we have to talk about the troponin tropomyosin these are acting as parents you guys you don't really have to write that down that's just the analogy but should troponin tropomyosin complex if you guys can abbreviate as TTC these block the binding sites of actin during a relaxed state block the binding sites of actin during the relaxed state block the binding sites of actin during a relaxed State okay so here we have this wonderful story drama for us okay you guys myosin is right here actin Trager the purple is the TTC so you guys can rest your hands for a second and we can start with once upon a time once upon a time there were two lovebirds it just so happened to be proteins myosin and actin and their love was where the greatest love story of all physiological history you guys is amazing and myosin and actin just wanted to get together and since it's peachy cuddle they just wanted to come okay they just want to become however acting had some protective parents called the troponin tropomyosin or the TTC's and they just would not let it and it would almost be like my son and so what you know myosin was plotting late at night it's like how am I gonna cuddle with and myosin became smart guy no I'm not the middle of story it's like with a projector going out right in the movie theater and so- day that he that he well first he found out that the troponin tropomyosin had a weakness or something called ice cream and ice cream has a lot of what we call calcium in it okay and he decided that he was gonna distract TTC with the calcium now to illustrate this story and you must use my arms as you guys can totally tell this is a perfect rendition of acting see this is a perfect rendition of myosin but I don't have a third arm so I can look at this one with the TTC's so what ends up happening is myosin brings in the ice cream and distracts the TTC's and guess what the calcium straps and binds to their bellies just enough to shift it out of the way and guess what happens literally as soon as bot myosin binds you guys to actin it creates a ratcheting effect immediately does this and what does that do to the overall length of the sarcomere it shortens it their love is so strong you guys that nothing can break them apart except this high-energy molecule called a teeny P now what you guys think about this it's a cheesy love story but kind of has its purpose here it's not just one - in head it's multiple myosin heads boom all ratchet as soon as they bind as soon as it ratchets it's so excited and to break that bond you need ATP so every little myosin head eats up an ATP molecule as soon as it releases the head naturally resets back grabs a little further and what does it do cuz he's so excited to return cuddles so essentially you guys boom boom boom boom boom and it happens faster magnets now my finger because now the finger I had to have all those little sarcomeres and those that's right it's anything we just like it's pretty crazy right and again you guys another reason why muscles produce so much heat why they're so expensive because every little myosin molecule to do this actually had to burn ATP to actually break the long not to actually cut to actually break the bond and then it resets and pulls further and you will eventually get something going from here to there now remember you guys sarcomere is stepped in to end with multiple sarcomeres so all these sarcomeres are shortening in unison and therefore shortened speed myofibril and therefore short is the muscle cell and therefore shortens the whole muscle which is again crazy training so I know right so one of the things that I want to do you guys is just kind of break that down on another page we are gonna skip 1:20 but come right back to it we're gonna go right to 1:21 just to kind of show you how this works so who is this as myosin right what are the red beads acting what's the purple GTC so this is relaxed you guys hear something like I always try to explain this if TTC wasn't there this is just chemistry these things just bond together they have an attraction of literally will bump you actually have to have TTC marek or the muscles would just they just love each other all the time right yeah all the cuddles in the world so what happens is you guys is calcium good so this is a relaxed state the next state you get is attachment what had to happen for attachments you write a calcium had to binds to TTC for attachment calcium had to binds to TTC and move it out of the way calcium in the body TTC get out of the way and I shouldn't say that you guys calcium has this ability to like yank and move things out of the way what happens a lot of times in chemicals bond or molecules bond together there's just a natural shape change and as soon as calcium just binds to change the shape just enough to roll it right out of the way and the next part is so as soon as it moves out of the way we don't binds but we know that myosin is so excited for this first date that he immediately comes the ratchets which is the power stroke which you could say shortens the sarcomere shortens the sarcomere okay you guys know the read the next part because we said their submission love what did you have to do to actually break that long depart ATP so when you guys see release and reset that requires ATP it's it's mind-boggling to me how fast this happens like like you can't even keep up with you guys I'm moving skeletal muscles right now just to do it just to talk and tell you about all these muscles in here just reset and it's crazy it's awesome yeah so they won't actually go back to as soon as they release they naturally go back partly because there's some protein we didn't talk about here there's actually some elastic proteins in here that kind of a natural recoil to kind of a relaxed state autumn is called tighten actually but um there are some proteins in there that actually do you have a kind of adjust or an elastic capability to go back a lot of times when you're just naturally moving you also will just have an antagonistic muscle pull the other direction there's natural extremes about to sometimes gravity doesn't for you you don't have it sounded point per second a slingshot me back to our relaxed state so but there is some little bit of natural elasticity to go back so super awesome I'm sure you guys have minds of bones that may be a little bit is there any questions before we go on 122 so 122 you guys is the last page we are going to go back a couple more to talk about motor units before we're done that's gonna be important but you have to get rid of the calcium so that you can relax because as long as calcium is in there binding to TTC we're going to get some contractions in literally you guys you have to pump the calcium out little calcium pumps you don't have to be for the names of these pumps but guess what the pumps from ATP you've littered so that's the other portion of this you have to pump the calcium out using energy from ATP so that's on the top of page 122 come to the calcium out using the TV yeah it's hard to sometimes you know sometimes it could be in their own though because we're going to talk about the neuron compartments if you're not going to calcium out oh yeah theory if the calcium is in there you can sustain contraction and most the time it's a nerve yeah it's a nerves that's misfiring so we energy source you guys it just mentions ATP again if you want to read that paragraph about hungry more than welcome to but you guys already know that in ATP is the energy source for the cell the key components of this or how that actually works the myosin and actin make sure you guys can identify these on a picture of the difference between minus and AB to the TTC which ones are thick thank you when you've got that filled out for you there but we need to step back because I skipped page one point and we kind of just talked about what it's actually happening into the muscle cell but you guys probably knew before you even walked into an advocate class how do you tell a Muslim Sikh attractants comes from your nervous system we gotta send the signal to them ELISA so we actually have to send a signal to the muscle cell to actually tell it to raise the calcium and that happens with the nervous system and so we're going to introduce this thing called the neuromuscular Junction and the motor okay so let me give you guys the definition of the motor unit first and then I'll give you the definition of a neuromuscular Junction so this is neuromuscular Junction or even these easier start with the motor unit so you need a textbook definition I'll show you a picture Lorien is motor neuron and the muscle cells controls motor neuron and a muscle cell the following question so in this case this whole thing you guys is the whole motor unit this is the motor neuron what do you think these guys are the muscle cells so this would be a 1 2 3 ratio you guys see that this actually doesn't exist in the human body this is just an example the smallest motor unit ratio is about 1 to 30 meaning that one motor neuron controls about 30 muscle cells usually small we have big ones they 1 motor neurons controlling 1,600 muscle cells and some keys and I'll kind of explain what that means in just a second now the neuromuscular Junction you guys it's just this part right here like it zoomed in right there it's where the actual motor neuron communicates with the muscle cell so you'd say communicate with muscle so it's kind of like it soon apps you guys like there's like for them to tell us muscle so we do its thing so true or false you guys the neuromuscular Junction that's part of the whole motor unit yeah that's partly because this is the whole motor this is their all-or-none principle all or nothing I'm gonna explain right now so the other nothing principle you guys alright in a second let me explain it first when this motor neuron sends a signal you guys it's controlling highly muscle cells in this make-believe example three I told you in other examples like the smallest one the human body's got one to thirty yeah so this is the stick it's not like this muscle cells gonna be a thumb break this muscle cells like I'm going to contract as ease ones like I'm feeling a bit of an old warrior that's not happens it's all or nothing this is really simple communication when this thing sends a signal all the muscle cells and controls will contract it full force that's the all or nothing principle so if you guys want me to write that up you say when motor neuron sends signal muscle cell is all muscles and try to force so let's conceptually talk about this first day you guys can rest your hands and it's the last thing a pretty much gonna do today and then so when I was over the University of Utah still teaching up there is the teaching assistant you had to do these things every Friday called Oakland where we got to have professors of different departments do presentations for us we had to give presentations and really cool it was our professors way of like keeping us from getting stagnant and not learning more about the body and during one of the presentations this really cool guy he actually did a ton of the sections that you get to see the pictures of my flash up here since Sean Miller and he grabbed one of my friends out of the audience and he blindfold him and he was doing a presentation on motor units Authority and recruitment and one of the things he did is he had all these paint buckets lined up but like the Home Depot buckets those bigger ones and so blindfolds my friends before my friends even those paint buckets are there and these paint buckets are just on the table just you know bro and he blindfolds him and because I've acacia left my translator down second so hands to handle any terms and elicits me kind of jerks it up because he doesn't know what it is when you figure down this mine okay I've got like some sort of a pocket right so then it goes to the next bucket it's about a quarter full of water flips it up goes next bucket half full of water lifts it up next bucket three-quarters full water lifts it up next bucket all the way full of water mix it up last bucket what do you think are you think that bucket went [Music] and so he was doing this to illustrate this point of what we call motor unit recruitment he was engaged in the same muscles but he was lifting more and more and more to get heavier weight and his point was about understanding motor units remember it's an all-or-nothing principle so with that being said you guys let's take the biceps for example thousands of muscle cells make up this whole muscle would it make sense to have one motor unit controlling all the muscle cells in my biceps why yeah so if I had one motor neuron controlling 100,000 muscle cells are all one bicep muscle cells every time that motor unit sends a signal what would happen for my sense pull force every time right and so do you guys see that every single muscle will be made up of molt you'll divide the muscle cells into multiple motor units so if you want to curl a little 10-pound weight I don't need 100% of my muscle cells right maybe one two motors do that and then I get another one you know and that's what we do my friend Chris is he just got him to recruit more and more motor units in there for more muscle cells to lift heavier and heavier weights and so that's a pretty awesome and cool thing how do you guys know how to do it you've lived life you kind of know how much things weigh and every once while you get a shocker maybe need a surprise where you see something on the floor you're like oh I think that's heavier than what it is and if you think it's heavier than it really is it comes up off the floor with a quick whoa if it's the opposite you think it's lighter than it is you do that thing where you going just come up I have a sixth sense of humor that with an avenue physiology and I have this dream that I want to go to like masa Fitness and change the 45 pound plates to be like might still haven't say 45 because that's how you figure out you know things you've looked at things like so let's kind of crazy you guys just some other factoids and then we'll kind of set class free for is the interesting thing is the average sedentary person can only recruit about 7080 percent of their motor minutes and this is going to be a test question this is kind of give you guys some cool ideas seventy percent so what I what to sedentary person and if somebody's not like working out or anything like that being judge you were just saying it's just kind of a definition here and what's what we say about that they can only engage about 7% of the moments on demand that means if you hook electrodes up to them and you tell them to lift as hard as they can as hard as they possibly can there are muscle cells in are not even engaging why in the world is that happening what is going on any guesses so you think it could it be muscle memory and there's probably a little bit but component to that the nervous system you guys doesn't trust you trust me either so what I'm gonna get you guys is it's neuromuscular inhibition and it's this thing to inhibit contractions because there are people who have pulled tendons off of bones before they have had injuries and things like that you can do the muscles can generate a ton of force and so it's this way of the nervous system protecting you until there's this wonderful chemical called adrenaline they get to push through your body and now instead of engaging only maybe 70% maybe you can engage about 100 percent that's a huge increase in strength on demand yeah so adrenaline will tell they're kind of override the nervous system inhibition that way usually event or training and we'll get to the training Department minute the other thing is so it's interesting you guys like my car fell on my hand when I was working on a pin between a jack stand in the way of my car and five guys lips my car and I lost me without Jack to get off and the promise channel is a real thing you guys have probably experienced it before in your life so I want you guys to think of the power of that now there's 650 there's some 750 plus muscles in the human body you skim off that overriding of the nervous system and then you have all that extra strength now the last thing that I was going to mention about that when I was lifting weights for the first time you guys can see it didn't really work but I wanted to be big and I was in high school they're not high school college music play and so for the first two months I'm lifting all these weights and I do my pride flex a thumbs cuz I think they should be proud of it and I wasn't really getting any bigger I thought the scale wasn't really getting any weight but I was getting stronger and one of the adaptations that happened you guys it's stronger neurologically your body allows your recruiting it's almost like your nervous system starts to trust you a little more so instead of engaging 70 alleging the age 75 up to 85 to 90 it's been a while since I'd rather did the most detailed research but I think the last night sometimes elite athletes people when training consistently for a while when you're around like 90 percent threshold and so even adrenalin still has an effect on on those people that's pretty crazy what happens if you stop working or being an Olympic event early so I think sometimes I don't know if they would I think they do get adrenaline and that probably does you see a lot of World Records done it competitions and stuff but again you wonder if people ever hit a full record while practicing but it's interesting to think about that's just one of the adaptations you guys get stronger your muscle cells will also literally get bigger mine didn't the book with the example that I was so it's pretty crazy remarkably there are training modalities and exercises that are just trained for your nervous system plyometrics for example is essentially a thing to recruit more more units with your mind working against your goal just because have your minds not started to kick in no I started to feel that short muscle producing know my muscle size my problem was I could have gained size at the same time that you wouldn't even enough yeah yeah it's a good protective mechanism that actually have I mean people who have adrenaline rushes come out sore sometimes damaged sometimes terriers and strings and stuff like that so anyway [Music] yeah I could have got me more stronger if I like increased size too so so hopefully you guys got everything if you have any questions on this stuff we can talk about we do have some extra time before we leave obviously [Music]