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Only A True Muscle Expert Can Pass This Quiz

Hope your brain is SWOLE.

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  1. 1. What is this big, rounded muscle called?

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    Correct! 
    Wrong! 

    This is the gluteus maximus!

    The gluteus maximus is the main superficial (outer) glute muscle, so it forms what you see of the booty! It starts at the coccyx (tailbone) and attaches to the femur and other bones in the leg. The gluteus maximus is one of the strongest muscles in the body and it's a major thigh extensor, meaning it allows the hip joint to extend and the thigh to rotate. So you use it to stand up, do squats, climb stairs, and a whole lot more.

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  2. 2. What is this upper arm muscle called?

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    Correct! 
    Wrong! 

    This is the biceps brachii!

    The biceps brachii is the main muscle in your upper arm, stretching from the shoulder joint to your elbow. It allows for extension at the elbow joint (so bending your arm) and rotation of the forearm so the palms face outwards. You can work the biceps with curls, but they also assist in rows, chin/pull-ups, and other moves.

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  3. 3. What would you call these two forearm muscles?

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    Correct! 
    Wrong! 

    These are the brachioradialis and the flexor carpi radialis!

    The brachioradialis is the bigger muscle on the outer forearm and the flexor carpi radialis is the smaller one on the inner forearm. The brachioradialis forms most of the fleshy part of the forearm and its primary function is to flex the forearm when lifting things. The flexor carpi radialis starts at the elbow and extends to the palm. It allows you to flex the wrist and move it back and forth. You'd exercise it by doing dumbbell or wrist curls.

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  4. 4. What is this muscle?

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    Correct! 
    Wrong! 

    This is the rectus abdominis!

    The rectus abdominis is the long, strap-like muscle that runs down the middle of the abdomen, from the sternum to the pubis — better known as the "abs." It's an important part of our core, which stabilizes us while we're standing and allows us to control our head, neck, and pelvis. The abs also help you sit up from a lying down position (like during ab exercises), facilitate bowel movements, and help push a baby out during childbirth.

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  5. 5. What are these muscles called?

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    Correct! 
    Wrong! 

    These are the hamstrings!

    The hamstrings are technically a group of three muscles: the semitendinosus, semimembranosus, and the biceps femoris. They run down the back of the thigh, from the buttocks to the knee. The hamstrings act to extend the thigh at the hip joint, flex the knee, and allow for thigh rotation. They're necessary for daily activities like walking, running, jumping, or dancing.

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  6. 6. Do you know the name of these back muscles?

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    Correct! 
    Wrong! 

    These are the teres muscles!

    The teres muscles (teres major and teres minor) are back muscles which stretch from the scalpula (shoulder) to the top of the humerus (upper arm bone). The teres muscles allow for rotation of the shoulder where it connects to the arm, and they help support the back and head when standing up. These muscles are important for activities like throwing a football, rowing, or basically anything involving the rotator cuff.

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  7. 7. What is this leg muscle called?

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    Correct! 
    Wrong! 

    This is the vastus medialis!

    The vastus medialis is a part of the quadriceps muscle group and runs the entire length of the thigh, ending above the patella (kneecap). It helps to extend the leg at the knee and stabilize the patella during activities like running or lunges. You can strengthen this muscle with exercises such as weighted squats and leg presses — and a stronger vastus medialis will stabilize the knee and prevent injury during exercise.

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  8. 8. What is this big back muscle?

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    Correct! 
    Wrong! 

    This is the trapezius!

    This big back muscle runs from the bottom of the head down the neck, to the top of the shoulders, and ends at the middle of the back — forming a "trapezoid" shape, hence the name. The trapezius allows for the shoulders to move, supports the arms, and can help keep the shoulders pulled back for good posture. Exercises like shrugs and raises will strengthen your traps.

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  9. 9. What are these two muscles called?

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    Correct! 
    Wrong! 

    These are the pectoralis major muscles!

    Don't be fooled by the boobs! Women have the exact same pectoral muscles as men — they just sit behind breast tissue. They extend from the clavicle (collarbone), and run down the sternum and the ribcage, connecting to the arms on the sides. The pecs help to flex and abduct the arms, and also pull the ribcage out when you inhale to expand the lungs so they fill with air. You can strengthen the pecs with exercises like presses and flyes.

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  10. 10. What are these two muscles called?

    decade3d / Getty Images / thinkstockphotos.com
    Correct! 
    Wrong! 

    These are the triceps brachii!

    The triceps brachii extend along the back of the upper arm from the scalpula to the elbow. They help extend the arm and stabilize the shoulder while it rotates. The triceps are used during big movements like push-ups, dips, or cable pushdowns and also small movements like writing.

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  11. 11. Can you name these muscles at the top of the arms?

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    Correct! 
    Wrong! 

    These are the deltoids!

    The deltoids form the rounded, fleshy part of your shoulders. They extend from the clavicle (collarbone), around the shoulder, and end at the humerus (upper arm bone). The deltoids allow for arm abduction and rotation, so you'd use them carry heavy things for a long period of time or do exercises like presses, reverse flyes, and lateral raises.

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  12. 12. What about these long muscles which run down the inner leg?

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    Correct! 
    Wrong! 

    This is the sartorius!

    The sartorius is a straplike muscle that runs along the inner thigh, starting from above the hip joint and ending just below the knee. It's the longest muscle in the body and it allows you to flex the femur (upper leg) and abduct the thigh, moving it out and away from the body. So it's the primary muscle involved in crossing your legs.

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  13. 13. Can you name these large back muscles?

    decade3d / Getty Images /thinkstockphotos.com
    Correct! 
    Wrong! 

    These are the latissimus dorsi!

    The latissimus dorsi (or "lats") are the widest muscles in the body, stretching from the bottom of the spine up to the shoulder muscles and wrapping around the width of the back. They help to extend, rotate, and abduct the upper arms — so to move them away from the body and backwards. The lats act opposite from the pecs, and you'd use them in activities like pull-ups, swimming, and climbing.

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  14. 14. What is the name of these muscles?

    decade3d / Getty Images / thinkstockphotos.com
    Correct! 
    Wrong! 

    These are the external obliques!

    The external obliques are symmetrical muscles which run along both sides of the abdomen. They allow you to rotate and move the trunk of your body while running or walking and they support the spine as it twists. Another important role of the obliques is to help compress the abdominal cavity, like when you need to curl in a ball to protect your vital organs.

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  15. 15. What is this muscle which runs along the inner thigh?

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    Correct! 
    Wrong! 

    This is the gracilis!

    The gracilis runs along the inner thigh, from the groin to the knees. It's used to move your thigh out and away from your body, flex your hip joint, and stabilize your knee. So it helps move the legs together when crossing them or sitting with your knees together.

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  16. 16. What's this muscle?

    decade3d / Getty Images / thinkstockphotos.com
    Correct! 
    Wrong! 

    This is the gluteus medius!

    The gluteus medius is in the outer, back region of the thighs, above the buttocks. It abducts and rotates the thigh, moving it out and away from the body, and provides support for the pelvis. This muscle keeps the pelvis from dropping while walking and supports thigh movement.

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  17. 17. What are these muscles?

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    Correct! 
    Wrong! 

    These are the tensor fasciae latae!

    The tensor fasciae latae is the prominent muscle of the outer thigh, stretching from the upper pelvis to the tibia, just below the knee. It allows you to flex the hip joint and abduct the thigh, moving it away from the body. These muscles help move each foot in front of the other while walking or running, and they keep the knee stable during lateral (side-to-side) movements. The tensor fasciae latae also keeps the pelvis stable on the legs during activities like skiing or horseback riding.

  18. 18. What is this big calf muscle called?

    decade3d / Getty Images / thinkstockphotos.com
    Correct! 
    Wrong! 

    This is the gastrocnemius!

    The gastrocnemius is the most prominent calf muscle and has two heads which stretch from the femur down to the knee. It allows the knee to bend by bringing the tibia toward the femur. It's very important for walking, running, pushing the pedals of a bicycle, and bending the knees to jump.

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  19. 19. Finally, what are these muscles on the front of the calf?

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    Correct! 
    Wrong! 

    These are the tibialis anterior and the peroneus longus!

    The tibialis anterior and peroneus longus make up the front of the calf, running from under the knee and down the shin to the ankle. The tibialis anterior allows the foot to flex and helps maintain your arches. You'd use it to "lock" the ankle when kicking a soccer ball or kicking while swimming. The peroneus longus runs along the outer side of the calf and also helps to flex the foot and stabilize the lower leg, like when you're standing on one foot.

    Via deacde3d / Thinkstock

Anatomical information sourced in part from:

-"The Princeton Review Anatomy Coloring Workbook," 3rd Edition, I. Edward Alcamo, PhD, Pengiun Random House 2012.

-The Medline Plus Information Database of The National Institute of Health (NIH) and U.S. National Library of Medicine.

-Healthline Human Body Maps 3D Visual Tool

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