Contrary to popular belief, you CAN build muscle as a vegetarian. The main hurdle you will have to overcome is the fact that protein aids in muscle building. The downside of course is that most people get the majority of their protein from animal sources. So how can you over come this? 1. Protein The perfect source of protein for most vegetarian body builders is Soy. Soy products like tofu, edamame, and soy milk are great because they offer all 8 essential amino acids that your body requires