It's very curious, but they use the egg, that is animal protein but the cow milk are changed with soya or another powder seed. The different forms of soya are the king and queen of this diet.
http://www.veganbodybuilding.com/?page=article_massbuildingMass-Building Nutrition Plan
by Robert Cheeke, Vegan Bodybuilder, February 28th, 2004
Here is a menu and eating schedule for a bodybuilder looking to gain mass.
7AM
2 cups oatmeal
2 vegan pancakes
soy protein drink
8oz soymilk
multivitamin supplement
10AM
soy jerky
soy protein smoothie (soymilk, protein powder, strawberries, banana, ice cubes)
4 soy yogurts
8oz orange juice with glutamine powder
1PM
4 slices of vegan pizza
soy protein smoothie (soymilk, protein powder, strawberries, banana, ice cubes)
tortilla and hummus
mixed nuts (almonds, peanuts, walnuts, hazelnuts)
4PM
soy crisps with almond butter
3 bananas
8oz soymilk
7PM
Baked tofu wedges
summer squash
refried beans
avacado
8oz pineapple juice with glutamine powder
10PM
soy protein smoothie (soymilk, protein powder, strawberries, banana, ice cubes)
2 soy yogurts
vitamin and mineral supplements