So, when designing one of my sentient demihuman species for my fantasy world, I designed them to have greater sexual dimorphism.
Astriads, as a species, are artificially [divinely] modified humans, with (red hair, purple eyes, multiple pairs of short horns, but that doesn't really matter, but more importantly:) naturally large musculature. While women are less affected, and are only "fit by default", all males, without any training, have by default a physique of a body builder, as well as being taller on average (200 cm average height, whereas women are only ~170 cm average height).
While there is also some self-strengthening temporary buff magic, I'd like to ignore it for a moment(it's only temporary after all), to know how much would the medieval/ancient soldiers benefit from that kind of naturally body physique. I'd also like to know if there also be any drawbacks to have army of sword/spear & shield, taller, Predator's Arnold physique, especially if their legs are quite muscled up too, (including that these males would obviously require far more callories to stay fed).
What I'm trying to ask is what impact would such a change have?
Edit: This is reality check in more ways than one, because honestly, what I'm describing is very close to an idea of "supersoldier" in many works of fiction. I just think the idea isn't developped well enough and fully thought through to all of its conclusions, so I want to get more complete understanding of drawbacks and advantages of "supersoldiers".