Not quite sure if this comes off as ridiculous, but do we have any evidence for actions taken in premodern armies to maintain good physical condition within the rank and file? If the soldiery spent most of their time marching, doing chores in camp, or conducting sieges, one would think that they'd experience severe muscular atrophy, especially with the poor diets that they would usually have to make due with (?) One would think, that this would be detrimental for their ability to fight, especially berfore the widespread use of firearms.