Plant-based food provides an adequate source of protein for humans including athletes.
There are strong beliefs, ideals, and myths that humans and athletes especially need lots of protein and this needs to come from animal sources like meat, fish, dairy, eggs and protein supplements.
Many studies show that just over 10% of calories from protein is enough to put athletes into nitrogen balance (one of the markers that show adequate protein balance). Research also reveals that higher percentages of protein intake decreases athletic performance. In addition, excess protein intake stresses the liver, kidney, and bones, which should all be performing on optimum level for athletes.
Studies as far back as 1904 with Yale athletes showed that when their daily protein intake was lowered from 100g to 64g, their athletic performance increased by 35%. Adults cannot increase muscle bulk by eating an excess amount of protein and any excess protein intake is actually converted and stored as fat. From this we can see that protein intake does not stimulate muscle growth and gaining muscle is always related to our lifestyle, genes, hormones, and the frequency of which the muscle is loaded, for example with resistance exercise and weightlifting.
Eating a plant-based diet provides 10-15% of calories from protein and as previously mentioned, this is the amount needed for muscle growth, increased energy, recovery, strength, endurance, and athletic performance. Therefore, a plant-based diet is an excellent source of nutrition for humans, including athletes. It is also free of the harming factors of other diets, for example the SAD diet (Standard American/Australian Diet), so the body can work at optimal performance, as it does not have to waste energy on dealing with the side-effects of the toxic overload that the SAD diet brings.