I mean meat is high on protein which is what you need to build muscle mass which is one of the requisites for being fit. Then running around all day chasing animals to eat them is gonna give you some really insane cardio, plus developed muscle from carrying around the prey and the hunting gear. So I have not idea what are you talking about, also pretty sure ancient humans already knew about edible plants and fungi.
I mean meat is high on protein which is what you need to build muscle mass which is one of the requisites for being fit. Then running around all day chasing animals to eat them is gonna give you some really insane cardio, plus developed muscle from carrying around the prey and the hunting gear. So I have not idea what are you talking about, also pretty sure ancient humans already knew about edible plants and fungi.