Comparing Vegetarian and Vegan Athletic Performance, Endurance, and Strength

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Few studies have investigated the impact of a plant-based diet on athletic performance, but the majority of the studies that have been done show no differences in endurance, performance, or strength. So, while plant-based diets do not seem to provide advantages or disadvantages on exercise performance, what plant-based diets can do is reduce the risk of chronic disease. This is a point I made in my video Why All Athletes Should Eat Plant-Based Diets, because surprisingly, endurance athletes may have more advanced atherosclerosis and more heart muscle damage, compared with sedentary individuals. So, it’s even more important they eat healthy. But due to the favorable impact on health, it could be assumed that performance would also be influenced by plant-based diets. Let’s take a closer look at the available evidence.

This is the most commonly cited review. Studies connecting vegetarian diets to improved health are well-established; however, the evidence for this phenomenon to be transferred to improved physical performance in athletes is less clear, finding no differences—at least acutely—between a vegetarian-based diet and an omnivorous diet in muscular power, muscular strength, short burst, or endurance performance. The intervention studies in this review, however, only lasted days or weeks. So, being a vegetarian for four days may not tip the balance, or even a few months, but that’s a considerable limitation. These are people who have been eating meat their whole lives, and subsequently adopt a vegetarian diet only for the duration of the study, rather than comparing participants who have adhered to a vegetarian or meat-containing diet long-term.

This study compared exercise capacity of vegan, vegetarian, and meat-eating recreational runners found similar maximum power output among all three groups––suggesting there’s no significant differences in maximum exercise capacity. But that’s at the same training frequency, time, and distance. Perhaps plant-based diets might enhance recovery, and allow such athletes to train longer and harder? A number of studies have come out since this review was published in 2016. What’s the update?

Well, this study compared the cardiorespiratory fitness and peak torque strength differences between vegetarian and omnivore endurance athletes. Most of the vegetarians were actually vegans, and most for at least two years, and…results from this study indicate that vegetarian endurance athletes’ cardiorespiratory fitness was greater than that for their omnivorous counterparts. They had a greater VO2 max, meaning a greater maximal oxygen uptake, greater aerobic capacity as measured on a progressive, graded, maximal treadmill test to exhaustion, though peak torque––peak strength based on leg extensions––didn’t differ between diet groups. Bottom line: these data suggest that vegetarian diets do not compromise performance outcomes, and may facilitate aerobic capacity in athletes.

In this 2020 study, all the plant-based participants were eating vegan for an average of four years. So, they were essentially comparing those who ate meat for 21 years versus those who ate meat for 25 years. But after four years eating plants, you might expect to see some sort of difference. Yet, no significant differences were noted for upper and lower body muscle strength, like in the last new study. Both groups of athletes were comparable for total body weight and lean body mass, though age was significantly higher in vegans compared with omnivores; so, that put them at a little disadvantage. Yet still, there it is again. Significantly better aerobic capacity. Then, they had them pedal until exhaustion, and the vegan group lasted about 25 percent longer—12 minutes as opposed to 9 minutes. Is that just because their aerobic capacity is so high? No, even after controlling for VO2 max levels, there was still a significant endurance advantage in the vegans. The researchers conclude that in the very least, a strictly plant-based diet doesn’t seem to be detrimental to endurance and muscle strength, and endurance might actually be better in vegans, contrary to popular belief.

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• Meyer NL, Reguant-Closa A, Nemecek T. Sustainable diets for athletes. Curr Nutr Rep. 2020;9(3):147-162.
• Barnard ND, Goldman DM, Loomis JF, et al. Plant-based diets for cardiovascular safety and performance in endurance sports. Nutrients. 2019;11(1):130.
• Nebl J, Haufe S, Eigendorf J, Wasserfurth P, Tegtbur U, Hahn A. Exercise capacity of vegan, lacto-ovo-vegetarian and omnivorous recreational runners. J Int Soc Sports Nutr. 2019;16(1):23.
• Craddock JC, Probst YC, Peoples GE. Vegetarian and omnivorous nutrition - comparing physical performance. Int J Sport Nutr Exerc Metab. 2016;26(3):212-220.
• Lynch H, Johnston C, Wharton C. Plant-based diets: considerations for environmental impact, protein quality, and exercise performance. Nutrients. 2018;10(12):1841.
• Lynch HM, Wharton CM, Johnston CS. Cardiorespiratory fitness and peak torque differences between vegetarian and omnivore endurance athletes: a cross-sectional study. Nutrients. 2016;8(11):726.
• Rogerson D. Vegan diets: practical advice for athletes and exercisers. J Int Soc Sports Nutr. 2017;14:36.
• Boutros GH, Landry-Duval MA, Garzon M, Karelis AD. Is a vegan diet detrimental to endurance and muscle strength? Eur J Clin Nutr. 2020;74(11):1550-1555.

Motion graphics by Avo Media

• atherosclerosis
• athletes
• chronic diseases
• muscle strength
• Plant-Based Diets
• vegans
• vegetarians