Opinion – Bruno Gualano: No meat, no muscle?

The athlete Milon of Croton (6th century BC) won the ancient Olympic Games half a dozen times, but his mythical aura owes much to his peculiar diet. Legend has it that the multi-champion used to eat 9 kilos of meat a day. Yes, per day. This would be the key to an impeccably muscular body, immortalized in sculptures scattered around the four corners, from the Louvre to Higienópolis.

Milon enthusiasts still believe that you don’t build muscle by eating plants, which vegetarians disagree with. Who is right? A new study led by my colleague Prof. Hamilton Roschel (University of São Paulo) ignited the debate once and for all.

Young men adhering to an omnivorous (which includes both plant and animal foods) or vegan (exclusively plant-based) diets were invited to participate in a 12-week bodybuilding program.

So that they didn’t lack the amount of protein needed for muscle development, omnivores and vegans received, respectively, milk or soy protein supplements.

In this way, the participants were aligned on the same starting point, with equivalent levels of dietary protein, as well as muscle mass and physical capacity. What differentiated them, therefore, was the nature of the diet: mixed or plant-based.

In line with the age-old belief in the anabolic powers of meat, we believed that vegans would respond less to bodybuilding stimuli than omnivores. But the evidence refuted us.

Regardless of the type of diet, participants who performed the specific exercise program gained strength and muscle in a very similar way.

It should be noted, however, that not every plant-based diet optimally supports adaptations to physical training. Notably, more restrictive diets (even omnivorous ones) can make it difficult to consume an optimal amount of protein — which, as we have seen, is a fundamental condition for building muscle.

Meat is a protein rich food. A single medium chicken breast fillet, for example, has about 30 grams of the nutrient. For an equivalent amount, approximately 1 kilo of cooked broccoli or 500 grams of beans would be needed.

Thus, people who do not eat meat and want to gain muscle usually need greater volume and diversity of foods to achieve the optimal amount of protein in the diet. Possible adjustments in the consumption of other nutrients, such as omega 3 and vitamin B12, are also important. Especially top athletes — who cannot afford to compete under any nutritional deficiencies — need, as a rule, the hand of a nutritionist.

None of this stops the growing wave of plant-based diet supporters in the sports world. Marta (soccer), Lewis Hamilton (auto racing), Chris Paul (basketball), Serena and Venus Williams (tennis) are just a few illustrious characters who, at some point in their careers, gave up meat. To note their performances, the lack of food does not seem to be a cucumber — to the taste of vegetarians.

And as for Milon’s carnivorous rage, what lesson can we learn? Well, I have not told you, dear reader, a revealing part of the mythology. The bad tongues said that the Greek drank no less than 10 liters of wine daily. Moralisms aside, was he or was he not a subject given to excess?