How Exactly Do Muscles Grow?

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The damaged cells release molecules known as ‘cytokines’, which call on the immune system of your body to repair the minor injuries. The immune system sends its ‘doctors’ to repair the damage and voila! You have just built stronger muscles!

If you’re a fitness freak, then you have already gone through a Herculean pile of articles and resources to find the answer to a very common, yet evasive, question: how do muscles grow? While you may have a decent understanding of methods and strategies to build muscles, we want to break down the actual process of muscle growth in small parts to understand it once and for all.

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Muscles All Over

muscles meme1

To many gym-goers, the only muscles in the body that matter are found in the arms, shoulders, chest, abdomen and legs, as these are the muscle groups that they work on endlessly for days, months or years. However, in reality, the human body consists of roughly 600 muscles. These muscles are present in every part of the body and facilitate every motor function that we perform throughout our lifetime.

human anatomy

Muscles constitute one-third of the weight of the human body (half the weight in some cases) and with the help of connective tissue, muscle tissue holds the body together. Ranging from the smallest twitch of a finger to lifting extreme weights, muscles are constantly in use, ready to react at a moment’s notice. Therefore, you should always take care of your muscles, whether or not body-building is your favorite pastime.

Also Read: Muscles – Contractile Machines Of The Human Body

Lifting Weight

Now, let’s talk about how muscles help you lift things, which is what most people at the gym seem to be practicing all the time.

It’s quite easy to lift light objects. Since only a few muscles are required to do the easy lifting, you can accomplish it by using only one hand. However, when an object is too heavy to lift using only one hand, multiple muscles in different parts of the body must be used to accomplish the task at hand (literally!).

Suppose you are raising a heavy sack filled with sand (try to think of a logical reasons to do so) off the ground. Provided you are not a heavyweight champion, it is very unlikely that you could lift it using one hand. A number of other muscles must be activated in your attempt; your belly tightens, your feet assume a stronger stance on the ground, your thighs tighten and your back tenses. All of these muscle movements collectively supply enough force to heave the sack off the ground.

How Muscles Are Built And Rebuilt

Since you put enormous pressure on multiple muscles in your body, the muscles fibers undergo a change at the cellular level; they actually experience infinitesimally small damage. The word ‘damage’ gives most people chills, as it is rarely a positive term, but rest assured, damage in this case is precisely what you need to grow muscles.

The damaged cells release molecules known as ‘cytokines’, which call on the immune system of your body to repair the minor injuries. The immune system sends its ‘doctors’ to repair the damage and voila! You have just built stronger muscles!

The more stress that’s put on the muscles, the more damage the muscle fibers experience and consequently, the more comprehensive the rebuilding of the muscles. The entire damage-repair cycle of muscles makes them more and more sturdy and improves their endurance when faced with constant and increasingly intense physical challenges.

There’s a good reason why they say that you should always be active; that way, you’re constantly putting your body, and thus your muscles, under stress, which ultimately leads to the improvement of your muscle mass. Turns out that stress is not always so bad, especially if you’re trying to look cut in the gym!

Also Read: We Use Facial Muscles All The Time, So Why Don’t They Build Up Like Other Muscles?

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References (click to expand)
  1. How Do Muscles Grow? - The University of New Mexico. The University of New Mexico
  2. Muscle Development. The University of California, Berkeley
  3. Muscle Growth. Grand Valley State University
  4. When you are lifting, how does it make your muscle strong .... The University of California, Santa Barbara
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About the Author

Ashish is a Science graduate (Bachelor of Science) from Punjabi University (India). He spearheads the content and editorial wing of ScienceABC and manages its official Youtube channel. He’s a Harry Potter fan and tries, in vain, to use spells and charms (Accio! [insert object name]) in real life to get things done. He totally gets why JRR Tolkien would create, from scratch, a language spoken by elves, and tries to bring the same passion in everything he does. A big admirer of Richard Feynman and Nikola Tesla, he obsesses over how thoroughly science dictates every aspect of life… in this universe, at least.