CPT Fitness NASM CPT Podcast

THE NASM-CPT PODCAST: How to Remember the Names of the Muscles

National Academy of Sports Medicine
National Academy of Sports Medicine
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One of the most common questions I get after a workshop is “how do you remember the names of all those muscles?” So, today we discuss anatomical words for muscles and from where they are derived. It’s important to learn the language of your profession and it’s simpler than you think! Muscles reviewed in this episode include:

  • Gastrocnemius
  • Soleus
  • Hamstrings
  • Semimembranosus / Semitendionsus
  • Biceps Femoris
  • Quadriceps
  • Rectus Abdominus
  • Gluteus Maximus
  • Iliopsoas
  • Trapezius
  • Rhomboids
  • Sternocleidomastoid

Check out the book “Carnal Knowledge” by Charles Hodgson and tune in to this episode of The NASM-CPT Podcast to learn roots for these anatomical body parts and how memorizing these them MAY not be as difficult as you once thought.

Get 20% off your order now by calling 800-460-6276 or visiting NASM.org, and using the code Podcast 20. 



What You'll Learn:

  • Muscles and where their names come from
  • Roots for muscles and how to memorize them

What Was Mentioned:



Welcome to the NASM-CPT Podcast. My name is Rick Richey and today we're gonna be talking about muscles and their names. Where do they get the names from? We're gonna talk about etymology and where these muscles derive their names from.

I'm gonna give you a couple places that you can go to. You can go to etymonline.com and find more about etymology, just about anything you wanna know, but I'm gonna suggest a book first. And it sounds like a book that maybe I shouldn't be suggesting, but it's called "Carnal Knowledge." Sounds shady, but it is a great book about the body and human anatomy and this guy that wrote it, Charles Hodgson, does a masterful job talking about where the names of these body parts came from and he makes it funny and interesting. It's entertaining, so you get a chance to read that book, get that book. It's really fantastic. And I'm pulling some of the information that I'm taking from today from that.

Now, every single thing that I do I'm gonna try to always have a little bit of research. So, the research I'm gonna pull today, and sometimes it's gonna have something to do with what we're doing and sometimes it's not gonna have anything to do with what we're talking about. But, today I'm gonna put this out there, is let's look at this. So, there's the Proceedings, it's a journal, Proceedings of the National Academy of Sciences of the United States of America. And they looked at exercise training and how it increases the size of the hippocampus and it improves our memory.

And this is done through aerobic activity and they did randomized control trials, 120 older adults, and they see increase in hippocampal volume. Now, the thing about the hippocampus is that it is where the consolidation of information gets shifted from short-term memory to long-term memory. And spatial memory which enables us to create navigation. That worked with trainers in the past that must have had very low hippocampal activity because they couldn't find any spatial awareness when they were at the gym.

But, for these purposes today, I think it's important for two reasons. One, it's gonna help us maybe if you do a little bit of exercise before you listen to the podcast, it's gonna help you remember, but two, hippocampus comes from the root word meaning seahorse. And that's just strange. But when people did the dissection of the brains, millennia ago basically, and they looked at it and they go, man that looks like a seahorse inside of the brain and they said, hey man, let's call it that. And they were like, yeah, let's call it that. So that's how it gets its name.

Well, this is how it works with almost every single muscle in the body. We have names that if you spoke Latin, they would seem like the most menial, the most nominal names that you could come up with. If you spoke Greek, it would seem like the most simplistic names, but we don't. We speak English, and basically what we've done now, is we've resorted to learning a different language. We're learning Latin names. We're learning Greek names in order to speak a language that we already have maybe an English name for.

But the reason that we do that is because English, as you may know, is a constantly evolving language. There are all these new words that are popping up. There are new conversations to be had. There's new additions to the lexicon. But for dead languages like Koine Greek and Latin, that are no longer being spoken, we can't change those and so we have a base where, if you're a medical professional, and somebody calls a body part something in another region, they call it something else, well, we can always go back to the Latin and say, can we agree that this is the body part.

Well, we're gonna do that today. We're gonna help you try to understand where the root of these words have come from and we'll also talk about the muscles and their joint actions a little bit as well.


So the first one I wanna talk about is my favorite one to talk about. It's called the gastrocnemius. And we're gonna do kind of major muscles, work from the bottom towards the top. And the gastrocnemius, you've heard that prefix, so gastroc. Maybe gastro and usually followed by intestinal. So gastro or gastroc comes from the root word belly. And so gastroc means belly and nemius means leg. So the literal translation of your gastrocnemius is belly leg.

Now, if you say, all right well, this makes total sense. You look at somebody from the side and your calf right there where the gastrocnemius, which is the larger one that's shaped like the belly, and somebody back in the day goes, man that looks like somebody's belly right there on the leg. And they're like, you know what, we're gonna call it that. And they all agreed on it and they started calling it belly leg. Except the term is gastrocnemius.

Now we don't think about these kind of nominal names that are coming across. We just say gastrocnemius and then we have another word for these muscles maybe in English when we put 'em all together and we call them calves, which we will be getting into why we call them the calves as well. A gastrocnemius crosses over the ankle joint and it can do plantar flexion, but it also crosses over the knee, and it can assist with knee flexion as well.


Now, let's go over to the other calf muscle. That one is called the soleus. And the soleus, you've ever heard of the sole of a shoe, right? Or the sole of your sandal. That's where that word's actually coming from. That the soleus or the sole of a shoe is the flat part of the shoe. A sole fish is a flat fish that probably looked to some fisherman like the sole of their shoes and they called it that. Well the soleus is a flat muscle and it lies underneath the gastrocnemius. So they looked at that and said that looks like the bottom of my sandal underneath that guy's gastrocnemius. Let's call it the soleus.

So underneath the belly leg is the bottom of a shoe. It's very simplistic when you start breaking it down. But you have to know the other language to know where it came from. These aren't hard words. It's hard because it can be a, it's a different language and we're just not familiar with this type of jargon. And jargon is actually a term that means language that is used within a specific group or community so we have medical jargon and that's really what we're going into, anatomical jargon, right now.

Joint actions for the soleus, plantar flexion basically. So it crosses over the heel, but it does not cross over the knee or any other major joints. So it does plantar flexion or it helps us to point the foot. Now, interestingly, when we put these two muscles together, they're called the calves. And the word calf comes from a young cow and the calving of a glacier is the large parent giving birth to a small offspring. So the root actually may have come from the same word in old Norse which is kalfi, starts with a k. So k-a-l-f-i, which means to swell or to give birth. So basically, the leg and that area looks like a pregnant belly and that's where the term calves came from.


Now, we're gonna move up on the posterior side of the leg there and we're gonna go into the hamstrings. Now, ham is the bend of the knee. And this was a phrase or a word that was used a long time ago and the first term, the first time ham came into the lexicon meant the back of the knee, where the knee bends. Well, in the back a knee, where the knees bend, there are a couple of cords that you could feel on the medial and lateral side of your legs and those were the hamstrings.

Now the strings of the bend of the knee are actually attached to muscles that go all the way up to the hip. So those strings actually started, then, to be referred to as the hamstrings and so the muscles became known as that. Now, these strings or cords on the back of the knee, it wasn't until like 700 years later that ham started to refer to the thigh of a pig. But for the longest time, it was the bend of the knee. Therefore, we get the name hamstrings.

Semimembranosus / Semitendionsus

Now, on hamstrings, there are three distinct different hamstrings. There's semimembranosus, and semitendinosus, which are the two muscles on the medial side, and then there's the biceps femoris, which is on the lateral side. Now, semi is Latin and it means half. So half of these two muscles, one is the membranosus, the other is the tendinosus. So membranosus is membrane, tendinosus is tendon, and that's where those get their names from.

Biceps Femoris

And then you get the biceps femoris. Well, we've talked about biceps before probably and we thought, oh the biceps, that means two heads. And then you have to understand the root word bi means two and we're all familiar with that, but the term ceps is the word for heads. So it is the two headed muscle on top of the femur. That is the biceps femoris, right.

All of these muscles do knee flexion. All of them do hip extension. Let's move on to the front side of the leg. We'll talk about the quadriceps and where that gets its name from. Quad means four and we talked just a moment ago that ceps means head so I've got these muscles that, four muscles, that all connect into one head.

Now, if you take your hand, you put it over the top of your kneecap, all of those muscles go into the common tendon there, that quadricep tendon and they run over the top of the kneecap. That's baffling to me. So if you rub it, it just basically feels like there is skin and then your patella, your kneecap. But that's actually an incredibly strong tendon that all the muscles in those big quads attach into and go over the top of that.


So, the quadriceps, there are four of them. Three of them have that root word, similar name, the prefix is vastus. So there's vastus medialis, vastus lateralis, and vastus intermedius. The term vastus, you've heard the term vast before and that means large or to a great extent. So there's a large medialis muscle. Medialis means medial or on the inside. Lateralis is lateral or on the outside. Intermedius means the one that's in between those two. So they are large muscles; one on the inside, one on the outside, and one between those two.

Rectus Femoris

And then you've got the rectus femoris. The term rectus, just the same thing for your abdominals, rectus abdominis and rectus femoris, rectus means straight. So the muscle runs straight up and down. Femoris means the femur, so the bone of the thigh, so it's the muscle that runs up and down on the front of the thigh bone. Now, all four of those cross over the knee and they do knee extension. But only the rectus femoris crosses the hip joint and it does hip flexion as well. So it is a two-joint muscle. The others are a one-joint muscle.

So the vastus family, medialis, lateralis, intermedius, they were wrecked by an intruder that came out, came in from the outside, the rectus femoris.

Rectus Abdominis

While we're here, let's just go ahead and talk rectus abdominis. Rectus means up and down, so straight line and abdominis means the belly on top of the abdominal region. So that's where the term rectus abdominis gets its name. Now, let's go a little bit lower.

Gluteus Maximus

We're gonna work our way back over to the glutes. There are three glute muscles. There's one really big one and there're a couple of smaller ones. And glute comes from a root word that just means rump or buttocks. So that was just the word that was used for the backside back in the day.

And there's a big glute called the maximus. There is a little glute called the minimus. And there is a muscle that's in between those two called the medius. So glute medius, medius just means middle. So it's in between the glute max and the glute medius. The glute maximus' primary movement's gonna be hip extension, but the way the fibers run, they also will externally rotate and abduct the hip.

Abduct means to move from medial to lateral. So we have this abduction, extension, external rotation. The glute medius will do abduction and posterior fibers external rotation. Glute minimus will do abduction of the hip and do a little bit of internal rotation on those anterior fibers as well.


You've got now a muscle called the iliopsoas, which we think about, it should be our primary hip flexor. Yes, the rectus femoris we just talked about is a hip flexor, but not a primary hip flexor. The iliopsoas is. Iliopsoas is the conjoining of two muscles into the same name. There's the iliacus and the psoas major. Now, when there's a major, there's probably a minor, but the thing is, not everybody has a psoas minor and it is just a smaller bundled muscle in the psoas.

When it is present, it has the same joint actions that take place for the psoas major. So, the psoas, which starts with a p by the way, p soas, is a, if you look at the root word, it is the muscle of the loins. So that muscle that's running onto from the hip and going into the spine, and it's underneath the abdominals.

And then, iliacus is a muscle that attaches to the ilium. And the ilium, if you were to take your hands, put 'em on your pelvis, they are the larger Mickey Mouse ears of the pelvis and they are on the inside of the pelvis. So glut medius is on the outside and the iliacus is on the inside of that. They have a common tendon and so these muscles go from the iliacus or the ilium and then the psoas from the lumbar spine, the transverse processes, the bodies, and all the way up to T12. They cross over the hip and they can do hip flexion primary action, but they can both also do a little bit of external rotation and slight bit of abduction. But that primary movement that you should think about with those is gonna be hip flexion.

Biceps Brachii

Now let's keep going 'cause I like to just-- Let's keep moving. Let's go to the arms. So we just did the legs. Let's do the arms. Biceps, biceps brachii. We've already talked about biceps means two heads and brachii means arm.

So biceps brachii just means the two-headed muscle that is attached to the arm. The brachialis muscle, which lies underneath the biceps, is the muscle of the arm. The brachii being the arm area above the forearm. So when we look at the language, we talk about arm as being the entire thing from our shoulder all the way down to our hands, but the arm technically is between the shoulder and the elbow and the forearm is from the elbow through the rest of the hand.

So brachii and brachialis referring to the area from the elbow to the shoulder. So we've got the biceps brachii. We have got the triceps brachii. So the root word tri is three. Like a tricycle is a three-wheeled bicycle. I don't know. I didn't say that right. But, you know what I'm talkin' about. So the triceps is a three-headed muscle that is on the brachii or on the arm. I like this one. This is one of my favorite ones.


The sternocleidomastoid. And we're now gone to the neck. So the sternocleidomastoid's a pretty superficial muscle and it kinda, it sticks out a little bit on the neck. So if you were to lie down flat and lift your head up, you'd feel it come out on the side of the neck. And it really, simplistically means sterno clavicle and mastoid process.

So the sternum is the breast bone and the cleido or cleido is the clavicle or the collar bone and the mastoid is that boney protuberance that is just behind the back of the ear. So you've got a muscle right here where-- When I first got a job as a personal trainer, I didn't have any experience as a personal trainer and I had a manager who wanted me to, wanted to test me.

And he would say things like, "Where is your rectus femoris?" And I would go, "Right there." And he'd go, "All right, cool. "Where is your quadratus lumborum?" And then I was like, "Right there," which I'm getting to. And then he said, "Where is your sternocleidomastoid." And I was like, "I have no idea." I had no idea what it meant. But I did immediately follow up with saying, "I don't know, but the sternum is here, "the clavicle is here, and the mastoid process is here." And he thought, "Man, that's good enough."

Quadratus Lumborum

So for somebody to figure that out based on the language that was present there. So we're going to go into, well, I mentioned QL, so let's talk about QL. QL is muscle, it's underneath. It goes from the top of the ilium on the posterior side into the transverse processes of the spine and into the lower ribs. And that quadratus lumborum is a muscle that, you gotta look at the quadratus just means four points. And lumborum referring to the lumbar spine. So it is the quad-shaped, that four quadriceps-shaped muscle that is on either side of the lumbar spine.

Erector Spinae

Now, let's look at the erector muscles. So we know that the muscles in the back, you may have heard of it, it's called the erector spinae. So the spinae is the spine and erectors means, when you erect a building, it means you are building a building. So it erects the spine or it builds up or lifts up the spine. So the language for these, really broken down, is relatively simple.


Now, let's go into the deltoid. I like the deltoid because it's a shape and we're gonna start getting into shapes right now. So the deltoid is that first one. So if you've ever heard of the Mississippi Delta. So the delta is just where the Mississippi River starts to go down on into the Gulf of Mexico, and as it does, the land gets much softer and so it spreads out and it creates a triangular shape as it starts to go into the water. Now a delta is a triangle. If you look at the symbol for the airline Delta, it is a triangle. It means triangle.

So delta is, or the deltoid, is a triangular-shaped muscle that's there on the shoulder. And we've got an anterior and a posterior and a medial deltoid which are just three different locations for these muscles to identify. Because they're on different parts of the body, they'll have different joint actions. So an anterior deltoid can create shoulder flexion and horizontal adduction. The middle deltoid can abduct in the frontal plane. And then the posterior deltoid can do horizontal adduction and a little bit of external rotation and extension. So we've got the deltoid, that triangular-shaped muscle that's on the shoulder.

Latissimus Dorsi

And then let's go, we'll go into pecs and then we'll get into, oh and lats. Oh, let's talk about lats. So the lats are a muscle that, you break it down. We say lats, but it comes from the word latissimus dorsi. And latissimus means the widest. So latissimus means widest and dorsi means on the back. And you've heard of a dorsal fin on a shark or a dolphin. So that is us, if we have that dorsal part of our body, that top part of our body when we're lying down flat, it would be the top part of our body, and we have the latissimus dorsi. That is on that part of our body, the dorsal side, the largest muscle.


So pectoralis. So pectoral. Pectoral. I'm gonna type it in right now 'cause I'm gonna make sure that I've got the right terminology here. Pectoral means pertaining to the breast or chest and we don't have an origin on this one, but there is a pectoralis major and a pectoralis minor. And we do know what those are.

There is a large muscle of the chest and there is a smaller muscle of the chest. So if the lats are doing moves like joint action, shoulder extension and they can do internal rotation of the shoulder, then the pec's primary movement is going to be shoulder horizontal adduction and internal rotation.

All of these muscles probably have a bit more joint actions in certain different areas, but for our purposes right now, we're just gonna keep it relatively simple and say lat's primary movement is going to be shoulder extension and the pec's primary movement is going to be horizontal adduction like what you would be doing in a bench press, and a typical bench press anyway.

So we've got the major muscles in the body there, but we're gonna hit a few more shapes. A couple more shapes are gonna be the trapezius and the rhomboids.


We know the trapezius muscles, we call traps and we usually think about the traps as just being the upper traps that do elevation of the scapula or shrug. But there are middle traps and there are lower traps, but the trapezius is one muscle and those middle traps do retraction and the lower traps do depressions. So some of them, the same muscle, have opposing joint actions. Upper traps elevate, lower traps depress the scapula, but it's all one muscle. And they help to, and they get their name from the shape. So the trapezoid shape is a quadrilateral shape that has a couple of parallel lines and shaped kind of like a diamond.


And you look at the term rhomboids which is a muscle that's superficial or underneath the trapezius, it is a rhomboid shape which is another quadrilateral shape and it is exactly what that sounds like. You're gonna look at it, it's gonna be shaped like a rhomboid, a little quadrilateral shape that's underneath it.

These names are simple, but complicated. They're simple, but it doesn't mean that they're easy. You almost have to really speak a language to understand a language. So using these words and these terms in your everyday conversation, people don't have to get it, but you need to speak it.

Start practicing using the words. Speaking these words, adding it into your conversation, and even sometimes with certain clients, teaching them. Because your clients don't really need to know necessarily what muscle they are working in order to work that muscle. It is important for you as a certified personal trainer for you to know what muscles you are working and what you're trying to address and what you're not trying to address, which I think is also incredibly valuable for us is to know what we're trying not to do as well.

Ultimately, we're trying to keep people safe and get them moving and those are the two requirements that I have starting off with anything. Safety first and then let's see if we can get people moving and then we can follow up on what are their goals ultimately. If they wanna lose weight. If they wanna increase performance. They wanna increase flexibility. But let's do this safely and let's get them there through movement and that's our job.

And we are understanding now the language of the words that we use in order to identify what these muscles are that create the movement. Now the future episodes, we're gonna go into finding out a little bit more about the language of anatomy and start referring to it more for our movement.

So we talk about some planes of motion, joint actions, and anatomical directions, and this'll be the basics of what we do in the beginning parts of the podcast in these episodes. And then we're gonna really push forward on looking at interesting things when it comes to high-intensity interval training. And what are some of the research, sprint training, the science of what's happening out there so that this podcast can be a resource for you as you go forward and start working with clients or you have students that you're working with and you wanna find unique ways to bring this information to students. Then I hope that this can be a support to you.

Also, if you wanna reach out to me, you can reach out to me at rick.richey@NASM.org and let me know what some of the topics are that you want to know about and we'll see if we can get an episode up or at least answer some questions in the episodes maybe at the beginning of the episode or at the end of the episode so we can answer questions that you have specifically based on exercise and what CPTs should be focusing on. We'll get into some business stuff soon, but for now, my name's Rick Richey, and this is the NASM-CPT Podcast.

The Author

National Academy of Sports Medicine

National Academy of Sports Medicine

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