A plant-based diet is often confused with a vegetarian or vegan diet; but in contrast to those, the plant-based diet can be characterized in the following ways:
- Focus on fruits, vegetables, whole grains, nuts, legumes, beans, seeds, and oils
- Less focus on animal foods but does not prohibit eating these foods
Choices are based on food mostly from plant sources – that’s it!
This type of diet has become a major new trend, as a growing number of people are recognizing the health advantages and food companies have begun to roll out plant-based meat substitutes, for example. However, due to the higher demands, doubts remain about whether a plant-based diet can sustain the performance of highly trained athletes.
Is it possible for trained athletes to adopt a plant-based diet without impairing their performance?
In a 1992 study of endurance performance, the physiological effects were investigated, comparing the performance of trained male athletes on an ovo-lacto-vegetarian diet to the performance of others on a mixed diet. Mixed diets included 15% of calories from protein, 27% from fats, and 58% from carbohydrates. The vegetarian diet included 14% of calories from protein, 28% from fats, and 58% from carbohydrates. Endurance athletes were investigated for 6 weeks, and the researchers found no significant difference in the performance of these athletes when compared to six weeks on a mixed or meat rich diet. There was only a small reduction in the total testosterone of athletes on a lacto-ovo vegetarian diet.
More recently, a cross-sectional study compared the performance of vegetarian and omnivore athletes. This study included assessments of the peak torque for leg extensions, maximal oxygen uptake (VO2 max), and body composition of 70 male and female endurance athletes, 43 of which were omnivores while 27 were vegetarian. Both groups consumed a similar quantity of protein that was within the range recommended for endurance athletes. The peak torque and leg flexion comparison didn’t show a significant difference, and neither did the VO2 max in males. But for females, the VO2 max showed high values for the vegetarian group (53.0 ± 6.9 mL/kg/min) and the omnivore group (47.1 ± 8.6 mL/kg/min).
Vegetarians are thought to have lower plasmatic carnitine concentrations than omnivores because they ingest fewer carnitine precursors. However, in one study that aimed to assess plasmatic carnitine and the physical performance of male vegetarians under basal conditions and after L-carnitine supplementation, the researchers didn’t find differences between the groups. After L-carnitine supplementation, the total plasma carnitine significantly increased (31% in vegetarians, 24% in omnivores), thus normalizing the plasma carnitine in vegetarians.
Plant-based versus animal-based protein for athletes:
The efficacy of plant-derived proteins is a key concern for athletic performance. Rice protein supplementation can be effective in replacing whey protein isolate. A clinical, randomized, double-blind study lasting 8 weeks evaluated 24 men who underwent resistance exercises and a periodized training protocol, and it showed that 48 grams of rice protein can be equally comparable with whey protein results in the performance of exercises and improvement of body composition.
Can plant-based diets improve athletic performance?
In contrast to many studies showing that a vegetarian diet does not result in differences compared to other diet types, a 2019 study showed better physical performance in a 6-minute walking test by participants with a higher vegetable protein intake. However, the researchers don’t know if this result was associated with the high protein intake itself or was perhaps a consequence of the other properties of plant-based foods.
A 2019 review showed that the plant-based diet can improve cardiovascular health, which is extremely important for endurance athletes; and in addition to improving performance, the plant-based diet also speeds up recovery time due to the antioxidant effects of the diet.
A plant-based diet improves human health:
The beneficial effects of exercise on physical health of all humans is well established in the literature. Recent reviews have shown that the plant-based diet can be equal to or better than the meat-based diet, as it has higher amounts of proteins of high biological value that meet the recommended needs of the human body.
For example, a study published in July 2020 demonstrated that a plant-based diet does not impair athletes’ performance while it improves the morphology and function of the heart. Therefore, a diet based on whole grains, fruits, vegetables, legumes, and nuts, with no or limited intake of animal products, is beneficial for everybody, not only athletes. This type of diet has been shown to be effective in preventing and managing type 2 diabetes, obesity, and cardiovascular disease.
For elite athletes, we can consider that a plant-based diet may not change their performance, but it improves their health. The International Association of Athletics Federations Consensus Statement 2019: Nutrition for Athletics indicates only a need for special attention to specific nutrients, such as iron.
Conclusion:
The plant-based diet has numerous benefits, potentially improving metabolic health and performance in resistance, power, and strength exercises, in addition to reducing the environmental impact of food production.