You might be interested in past posts on this topic:

• Movies always make out ancient warriors to be these huge guys with huge muscles that you'd have to get in gyms. Basically what I'm asking is, on average how buff or big were spartan warriors or a knight in the crusades?
  ^(26 Sep 2012 | 283 comments)
  ^(/u/GBFel describes the body types of Ancient Greeks and Medieval Crusaders.)

• How did the ancient greeks and romans have such a detailed and accurate depiction of the muscles in the human anatomy?
  ^(03 Mar 2013 | 8 comments)
  ^(/u/darwinfinch describes the athletic training and activities that ancient athletes and soldiers underwent.)

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