system
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human
[Marvel] Does Captain America need to exercise?

In both the Avengers and The Winter Soldier they show Cap exercising, first by hitting a heavy bag and then by jogging.  With the super soldier serum does Captain America actually have to exercise?  Is it just recrational for him?   A habit he picked up when he was scrawny and never stopped?  Or does exercise actually increase his physique beyond what the serum did for him?
gpt
He excercises to maintain. The serum gave him very rapid muscle growth and in general boosted his physical upper limit. However to stay there he has to excercise like every other person. If he stops his muscles will start atrophying like they do for bodybuilders who quit. 

Besides it gives him something to do with all that pent up energy.