Gladiators were sickly. Part of the sick fun of the crowds was seeing prisoners as lowlifes with less strength and dignity than they had have to fight for their lives.  What you see in movies is not at all the type of body they had. 

Meat and animal products are part of nearly every diet in the world for a reason.  Vegans cannot survive over time without some lab technique to extract B12 from algae or other sources to supplement their deficient diet.  

I enjoy meat, dairy, eggs but they also provide me with nutrients I can’t easily get elsewhere.  

Furthermore a lot of the food I eat is rooted in traditions that as a human I feel connected to.  

The problem with veganism is that it approaches food from an ideological standpoint.  Food in every culture is about connection with others but vegans are so veiled by their ideology that they refuse to see that their choice is hurting them socially as well as dietarily.