Many top athletes have moved to vegan diets purely to give them a competitive edge in their sports, and more are continually following this trend. The move is strategic. The American ultra-marathon runner, Scott Jurek, began his transition to a vegan diet as a long-term solution to avoid a family history of chronic disease according to his interview in GQ magazine ( https://www.gq.com/story/the-real-life-diet-of-the-ultramarathoner-who-gave-up-meat-and-became-vegan ). In his interview he is quoted as saying “If [athletes] aren’t fueled properly, they don’t have great results”.
As well as top runners, there are top body builders, tennis players, cyclists, fighters, and many others who at the top of their game have seen the benefits in a vegan diet (https://www.businessinsider.com/elite-athletes-who-are-vegan-and-what-made-them-switch-their-diet-2017-10 ). This is all about top performers wanting top performance from their bodies.
Vegan strong-man Patrik Baboumian is one of the strongest men in the world. In 2011 he was named Germany’s strongest man and in 2012 won the European Powerlifting Championships. You can read about what he eats in a day here (https://barbend.com/vegan-strongman-patrik-baboumian-diet/) and about other vegan strongmen here ( https://barbend.com/strongest-vegans-on-earth )