You look at your muscles every day. You work out to boost your gains, increase your muscle size, and enhance your strength and performance. With all that hard work, it’s a wonder how little people truly know about their muscles.

Well grab your backpack because you’re about to go to school. Check out these 40 little known facts about the muscles in your body:

    1. Because contracting biceps were once thought to resemble mice crawling under a rug, the word “muscle” stems from the Latin “musculus” which meant “little mouse.”
    2. There are over 600 muscles in the human body. If every one of your hundreds of muscles pulled in the same direction all at once, you could lift over 25 tons.
    3. There are no muscles “in” your hand, only tendons, ligaments, and bones. Your fingers move when your forearm muscle pulls on those other connective tissues.
    4. Your eye muscles move over 100,000 times a day, most rapidly during deep sleep.
    5. The one muscle that is working every second of every day from the moment you are born to the day you die? Your heart muscle . . . and it never tires.
    6. In one day your heart muscle will pump an estimated 2,000 – 2,500 gallons of blood around a system of blood vessels in your body that is believe to be 60,000 miles long.
    7. Muscle memory is a real thing. With the same repeated practice of the same motions and movements, your brain needs less and less processing time to cue your muscles to do what you want. Thus, practice can make perfect, but bad habits (like improper squatting form) can also be hard to break. (Read This: How to Hack the Deadlift)
    8. Artificial muscles have been engineered in a lab at the University of Texas, Dallas and can lift 100 times what a normal human muscle can.
    9. Shivering in the cold? This is your body’s way of warming you up – naturally contracting your muscles over and over.
    10. Muscle contraction plays an important role in maintaining your body temperature; close to 85% of the total heat generated in your body is from muscle contraction.
    11. The tiniest skeletal muscle can be found in the ear, the stapedius – it assists in stabilizing the stapes, a tiny bone in the inner ear which helps conduct sound vibrations.
    12. All the muscle fibers you have are the ones you were born with – they simply grow thicker over time.
    13. There are 3 different types of muscles in your body. Skeletal (those attached to your bones), smooth (involuntary muscles in your gut, bladder, blood vessels, etc.), and cardiac (those in your heart).
    14. The Palmaris longus, a tendon which runs along the middle of your forearm to your wrist is missing in about 10 to 15% of the human population – to do a quick check if you have one, click here.
    15. The largest muscle in your body is the gluteus maximus, that big muscle in your buttocks. It largely supports your posture and your ability to walk up and down stairs.
    16. One of the strongest muscles in your body is actually in your mouth and controls your jaw, the masseter(s). They can close with a force of 200 lbs in humans, and are only found in mammals.
    17. The old adage, “Frowning employs over 40 muscles while smiling only uses 17” isn’t scientifically proven, however, the mantra of optimism is worth its repeat.
    18. Trying to hit your 10,000 steps goal each day? You are using close to 200 muscles in your body with each single step.
    19. While ligaments connect one bone to another (like in your knee joint, for example), tendons, on the other hand, have the responsibility of connecting muscles to bone and other body parts (like your eyeballs!)
    20. Most vertebrates including humans have a muscle mass that makes up roughly 35 to 40% of their total body weight.
    21. Tissue strands, fascicles, which make up skeletal muscles are actually grouped bundles of myofibrils, which are themselves simply millions of sarcomeres laid end to end. Sarcomeres are comprised of overlapping thick and thin myofilaments, which at their biological core are strands of protein molecules (mostly actin and myosin).
    22. The motor cortex region of your brain controls muscle movement with the right side of the motor cortex controlling the left side of your body, and the left side of the motor cortex controlling your right side.
    23. Voluntary muscle movement is the result of a signal being sent from the brain, through the spinal cord, and out through the peripheral nervous system to the muscles.
    24. Muscle movement typically happens in pairs, and is called reciprocal inhibition, where a reflexive contraction (stretch) in the agonist muscle is accompanied by a relaxation in the antagonist muscle.
    25. Muscles never actually push, they can only pull. When you are “pushing” something like a door open, your arm and shoulder are actually pulling back on your elbow.
    26. Skeletal muscles are physiologically referred to as “striated” for the light and dark muscle fibers that appear as stripes.
    27. Smooth muscles in your digestive system continuously contract and relax to help move food through digestion. (Read This: Anabolic Eating: How to Increase Testosterone Naturally)
    28. The longest muscle in the body is the sartorius muscle which runs from the hip down your thigh to your lower leg for about 30 cm – it helps rotate, adduct, and flex the hip.
    29. When you sleep, your body relaxes muscles to boost blood flow to them, and releases hormones which aid tissue repair and growth – sleep is critical for building muscle after a workout.
    30. Genetics can play a role in how fast and how much muscle you gain through training – studies have shown the activation of “satellite cells” which help repair and rebuild muscles can vary from person to person.
    31. Muscles are more metabolically active than fat which simply means they burn more calories than fat. Even at rest, a muscle will burn calories.
    32. Humans could hear their muscles moving if they had the ability to hear below 20 hz.
    33. Muscle relief cream includes topical creams, gels, ointments and salves that provide an analgesic effect to muscles, boosting blood flow and actually “distracting” the brain from pain with heating and cooling sensations from ingredients like menthol or capsaicin.
    34. As you fall asleep and your muscles relax, sometimes your brain misinterprets this as “falling” and cues the twitching and jerking sensation your experience in an effort to “rebalance” you, also known as a hypnic jerk.
    35. The tongue is made up of 8 different muscles all intertwined to form what is known as a muscular hydrostat, and they are the only muscles to work independently of the skeleton (think about all the talking, chewing, swallowing, etc!).
    36. Muscle tissue is roughly 15% denser than fat tissue, but that doesn’t mean it weight more. It simply takes up less space than fat.
    37. There are 43 muscles in the face, most of which are controlled by the facial nerve which channels out the cerebral cortex to exit the skull right in front of your ears.
    38. There are over 100 muscles in each of your feet (in addition to 26 bones and 33 joints).
    39. 3 muscles are used for blinking and adults blink anywhere from 10 to 20 times a minute, that is upwards of over 16,000 blinks a day.
    40. Skeletal muscle fibers are categorized into two groups: fast twitch and slow twitch. Fast twitch muscles fatigue faster but support rapid sprints and high intensity movement. Slow twitch muscles enable more long-endurance activity like long distance running.


About the Author
Joe Fleming is the President at ViveHealth.com. Interested in all things related to living a healthy lifestyle, he enjoys sharing and expressing his passion through writing. Working to motivate others and defeat aging stereotypes, Joe uses his writing to help all people overcome the obstacles of life. Covering topics that range from physical health, wellness, and aging all the way to social, news, and inspirational pieces…the goal is help others “rebel against age”.