eli5: why do muscles stop hurting when you exercise consistently when they’re still growing?

Question

eli5: why do muscles stop hurting when you exercise consistently when they’re still growing?

In: 8

Answer 1

The pain is tiny tears in the muscle fibers and lactic acid build up.

These things are always the worst when a body is pushed far beyond what it is accustomed to.

But when a body becomes accustomed to strenuous workouts, it adapts to counteract these ill-effects. Muscle fibers become more stretchy and pliable, resulting in fewer tears. Also, the muscle tissue grows, so there are more fibers than before to spread out the load of the work being done. Each fiber is asked to do less work because there are so many more fibers.

And the body also produces less lactic acid, and what it does produce is processed faster to alleviate the negative effects it has.