What actually is a muscle flexing and does it serve any biological purpose?


What actually is a muscle flexing and does it serve any biological purpose?

In: Biology

When you flex your muscles they are going from being long and thin to shirt and thick and in doing so move whatever other parts of your body they are attached to. The purpose is to make your body move. You can think of it sort of like a rubber band, but reverse because muscles are long and thin when relaxes and rubber is short and thick.

When you flex a muscle, it moves. This moves the tendon it’s attached to, and that moves the bone that tendon is attached to. So flexing a muscle is how we move our bodies.

If you’re referencing the act of just flexing to flex and make a muscle look bigger, you’re actually flexing opposing muscles. If you flex your bicep to make it look bigger but not move your arm, you are actually playing tug of war with your bicep and tricep and don’t even know you’re doing it. The bicep flexes to pull the arm back, but the tricep also flexes to keep that arm in place at the same time.

Technically muscles do not flex–only joints flex. Muscles contract, or shorten, to move the bones of your body and allow movement and locomotion.

You may be referring to what body builders do to show off. That is simply contracting both the agonist and antagonist muscles so that both look more prominent. That action is always happening every time you move–they just exaggerate it. The purpose is so that the agonist muscle doesn’t snap your joints–the antagonist always balances it.