Athletes require a diet that is tailored to their nutritional needs for the specific sport they are participating in. Proper energy intake and nutrition is essential for optimal sporting performance, recovery, reduced risk of injury, fatigue, and illness (Thomas et al., 2016).
In modern times, meat has been touted as an indispensable part of an athlete’s diet. However, recently more light is being shone on the performance-enhancing and health benefits of vegetarian athletes.
In ancient times, it is believed that gladiators followed a plant-based diet. Analysis of the bones of ancient gladiators of Rome, has shown that their diets may have consisted largely of plant-based foods such as barley, wheat, peas, and lentils. According to Longo et al. (2008), “The best fighters in the ancient world were essentially vegetarian”.
In this article we explain (in plain English!) the conclusions of scientific studies that have looked at vegetarian athletes.
Vegetarian diets consist of plant-based foods rich in whole grains, legumes, nuts, seeds, fruits, and vegetables, while avoiding red meat, processed meat products, refined foods, and sweets.
There are several variations of a vegetarian diet:
Drawbacks of Vegetarian Athletes
Athletes who follow a strict vegetarian diet, limiting dairy, meat and eggs are at a greater risk of developing nutrient deficiencies such as iron, zinc, calcium, vitamin D and vitamin B12 “due to these dietary restrictions, athletes are at a higher risk for several micronutrient deficiencies including omega-3, iron, zinc, iodine, calcium, vitamin D, and vitamin B12” (Fuhrman & Ferreri, 2010).
Benefits of Vegetarian Athletes
Despite the drawbacks of vegetarian athletes covered in the previous section, numerous studies have reported the many health benefits of vegetarian athletes.
In the sections that follow we highlight studies that have linked vegetarian athletes with physical benefits such as:
According to the Academy of Nutrition and Dietetics “An appropriately planned vegetarian, including vegan, diets are healthful, nutritionally adequate, and may provide health benefits for the prevention and treatment of certain diseases. These diets are appropriate for all stages of the life cycle, including pregnancy, lactation, infancy, childhood, adolescence, older adulthood, and for athletes” (Melina et al., 2016).
According to a study published in the journal, Sports Science Exchange “Athletes at all levels of competition can meet their energy and nutrient needs on a vegetarian or vegan diet that contains a variety of foods, including grain products, fruits, vegetables, protein-rich plant foods, and (if desired) dairy products and eggs” (Larson-Meyer, 2018).
A vegetarian diet is able to provide athletes with the same physical performance abilities as an omnivorous diet.
A review published in the International Journal of Sport Nutrition and Exercise Metabolism, investigated the association between a plant-based diet and improved physical performance (strength, speed, endurance and power). Of the 8 studies analysed, there was no evidence to suggest that vegetarian athletes had poorer physical performance to omnivorous athletes “No distinguished differences between vegetarian-based diets and omnivorous mixed diets were identified when physical performance was compared. Consuming a predominately vegetarian-based diet did not improve nor hinder performance in athletes” (Craddock et al., 2015).
Scientists from Arizona State University, investigated the impact of vegetarian and omnivorous diets on athletic performance of endurance athletes. Athletic performance was measured using VO2 max (peak oxygen uptake) and strength testing. Results indicate that vegetarian athletes had similar athletic performance to their omnivorous counterparts “Results from this study indicate that vegetarian endurance athletes’ cardiorespiratory fitness was greater than that for their omnivorous counterparts, but that peak torque did not differ between diet groups. These data suggest that vegetarian diets do not compromise performance outcomes and may facilitate aerobic capacity in athletes” (Lynch et al., 2016).
A study published in the Science of Gymnastics Journal, evaluated the effectiveness of a vegan diet for competitive artistic gymnasts. They found that a well-planned vegan diet was an appropriate and healthy diet for competitive gymnasts “evidence of a wide range of benefits of a well-planned vegan diet and the energy and nutritional needs of a competitive gymnast for a variety of goals (support of the strenuous and repeated training with gymnastics apparatus or in all-around gymnastics, effective recovery, simple control of appropriate body weight, and long-term health)” (Jakse & Jakse, 2018).
A study published in the Journal of the International Society of Sports Nutrition, evaluated the exercise capacity (maximum power output and lactate concentration) of vegan, lacto-ovo-vegetarian and omnivorous recreational runners “The data indicate that each examined diet has neither advantages nor disadvantages with regard to exercise capacity. These results suggest that a vegan diet can be a suitable alternative for ambitious recreational runners” (Nebl et al., 2019).
Notable Professional Vegetarian Athletes
Notable vegan athletes who are participants in various professional sporting disciplines, from high-level endurance to power and strength are listed below:
Vegetarianism is capable of providing elite and professional athletes with the power, strength, endurance, and overall sporting ability required to reach success on an international stage (Wirnitzer, 2020).
Plant-Protein versus Animal-Protein
Protein quality and quantity is an important aspect of an athlete’s nutrition. Plant-based protein supplements may provide the same physical benefits to athletes as its animal-based protein counterparts.
According to a study published in the journal, Nutrients, plant protein provides similar outcomes to animal protein for athletes “consumption of a plant protein source in an efficacious dose (typically larger than an animal protein) can instigate similar and favourable changes in amino acid update, muscle protein synthesis rates, and exercise training adaptations such as strength and body composition as well as recovery” (Kerksick et al., 2021).
A study published in the International Journal of Environmental Research and Public Health, analysed the effect of whey protein and soy protein on lean body mass and strength during a 12-week resistance training program. Soy protein was able to provide similar results to whey protein “plant protein can support strength and muscle development comparably to whey protein, when consumed in amounts that provide sufficient leucine” (Lynch et al., 2020).
A study published in the journal, Sports, evaluated the effectiveness of animal-based protein (whey protein) and plant-based protein (pea protein) on physical adaptions after an 8-week period of high-intensity functional training (HIFT). Plant-based protein provided the same results as the animal-based protein “ingestion of whey and pea protein produce similar outcomes in measurements of body composition, muscle thickness, force production, workout of the day (WOD) performance and strength following 8-weeks of HIFT” (Banaszek et al., 2019).
A study published in the International Journal of Sport Nutrition and Exercise Metabolism, compared the effectiveness of soy protein to animal protein on muscle mass gain and strength in resistance exercise training (RET). They found no difference between soy and animal protein on muscle mass gain and strength following RET “soy foods and soy protein supplements can be viewed as sources of protein suitable for building strength and increasing lean tissue in response to RET” (Messina et al., 2018).
Mechanisms for Improved Athletic Performance
There are various mechanisms which have been thought to play a role in the improved physical health and sporting performance of vegetarian athletes. They are as follows:
Cardiovascular health is essential for athletes, especially endurance athletes. Plant-based diets may provide cardiovascular health benefits to athletes, through leaner body weight, improved blood pressure, blood glucose control, and plasma lipid concentrations.
A review published in the journal, Nutrients, analysed studies which looked at the ability of plant-based diets to reduce cardiovascular risk factors, and affect performance of endurance athletes. “Plant-based diets play a key role in cardiovascular health, which is critical for endurance athletes. Specifically, these diets improve plasma lipid concentrations, blood pressure, body weight, and blood glucose control, and, as part of a healthful lifestyle, have been shown to reverse atherosclerosis” (Barnard et al., 2019).
A study published in the journal, JAMA, reported that vegetarian diets are beneficial for cardiovascular health “a low-fat vegetarian diet has been shown to reverse coronary atherosclerosis, increasing blood flow and reducing the risk of coronary events” (Ornish et al., 1998).
Reduced Inflammation and Oxidative Stress
Oxidative stress occurs when there is an overload of free-radicals in the body, and the body’s immune system is unable to neutralize them. Although exercise has shown many health benefits, exercise can also lead to oxidative stress.
Plant-based diets which are abundant in antioxidants and anti-inflammatory compounds may prevent exercise-induced oxidative stress.
A review published in the Journal of Sport Sciences, investigated the effectiveness of a vegetarian diet to reduce exercise-induced oxidative stress. They concluded that vegetarians could have an advantage to reduce exercise-induced oxidative stress due to the abundance of antioxidants in a vegetarian diet “vegetarians may have an enhanced antioxidant defence system to counter exercise-induced oxidative stress due to the increased quantities of fruit, vegetables, and wholegrains they consume” (Trapp et al., 2010).
A review published in the Asian Journal of Sports Medicine, investigated association between exercise-induced oxidative stress and dietary antioxidants. They found that healthful vegetarian diets were effective against exercise-induced oxidative stress “Regular consumption of various fresh fruits and vegetables, whole grains, legumes and beans, sprouts and seeds is an effective and safe way to meet all antioxidant requirements in physically active persons and athletes” (Yavari et al., 2015).
To conclude, a vegetarian diet is able to provide athletes with the nutrition they need to perform and be successful in their specific sporting discipline, whether it be an ultra-marathon runner, or a gymnast. Plant-based protein is able to provide the protein quality and quantity, comparable to animal-based protein.
A vegetarian diet is able to provide the same physical performance ability as a diet which contains animal protein, with the advantage of a healthier heart and reduced exercise-induced oxidative stress due to the abundance of antioxidants present in plant-based foods.
Potential risks for vegetarian athletes include higher risk of nutrient deficiencies and inadequate energy intake. Vegetarian athletes should consult with a sports dietitian to ensure that they are meeting their energy intake and nutrient needs for that particular sports activity.
A well-planned, balanced vegetarian diet, with close monitoring for nutrient deficiencies is able to provide athletes with the nutrients they need, even for ultra-endurance athletes.
According to Wirnitzer (2020), “A well-planned vitamin B12 supplemented and diligently implemented vegan diet promotes building muscle mass and strength, and a good state of health for athletes. Vegan diets applied to sports-related dietary tactics are compatible with high performance and competitive sports”.
Athletes Benefits Studies
Benefits for Athletes
Name of Paper
Link to Paper
Benefits of a plant-based diet and considerations for the athlete
European Journal of Applied Physiology
High-Protein Plant-Based Diet Versus a Protein-Matched Omnivorous Diet to Support Resistance Training Adaptations: A Comparison Between Habitual Vegans and Omnivores
Plant Proteins and Exercise: What Role Can Plant Proteins Have in Promoting Adaptations to Exercise?
Update on vegetarian and vegan athletes: a review
Journal of Physical Fitness and Sports Medicine
Efficacy of Popular Diets Applied by Endurance Athletes on Sports Performance: Beneficial or Detrimental? A Narrative Review
The Effect of Dietary Structure on the Health Status of Athletes
International Conference on Social Development and Media Communications
How the vegetarian diet influences recreational and professional athletes’ physical performance: A systematic review
Research, Society and Development
Potato Protein Isolate Stimulates Muscle Protein Synthesis at Rest and with Resistance Exercise in Young Women
Vegan Diet in Sports and Exercise - Health Benefits and Advantages to Athletes and Physically Active People: A Narrative
International Journal of Sports and Exercise Medicine
A Vegan Athlete’s Heart—Is It Different? Morphology and Function in Echocardiography
Plant-based eating patterns and endurance performance: A focus on inflammation, oxidative stress and immune responses
No Significant Differences in Muscle Growth and Strength Development When Consuming Soy and Whey Protein Supplements Matched for Leucine Following a 12 Week Resistance Training Program in Men and Women: A Randomized Trial
Environmental Research and Public Health
Exercise capacity of vegan, lacto-ovo-vegetarian and omnivorous recreational runners
Journal of the International Society of Sports Nutrition
Chapter 8 - Vegetarian Athletes
Nutrition and Enhanced Sports Performance (2nd Edition)
The Effects of Whey vs. Pea Protein on Physical Adaptations Following 8-Weeks of High-Intensity Functional Training (HIFT): A Pilot Study
Plant-Based Diets for Cardiovascular Safety and Performance in Endurance Sports
Plant-Based Diets: Considerations for Environmental Impact, Protein Quality, and Exercise Performance
VEGETARIAN AND VEGAN DIETS FOR ATHLETIC TRAINING AND PERFORMANCE
Sport Science Exchange
No Difference Between the Effects of Supplementing With Soy Protein Versus Animal Protein on Gains in Muscle Mass and Strength in Response to Resistance Exercise
International Journal of Sports Nutrition and Exercise Metabolism
IS VEGAN DIET APPROPRIATE FOR COMPETITIVE ARTISTIC GYMNASTS?
Science of Gymnastics Journal
Novak Djokovic: ´I am vegan!´
News Article: Tennis World
Cardiorespiratory Fitness and Peak Torque Differences between Vegetarian and Omnivore Endurance Athletes: A Cross-Sectional Study
Vegetarian and Omnivorous Nutrition—Comparing Physical Performance
International Journal of Sports Nutrition and Exercise Metabolism
Exercise-Induced Oxidative Stress and Dietary Antioxidants
Asian Journal of Sports Medicine
Vegan Triple-Ironman (Raw Vegetables/Fruits)
Case Reports in Cardiology
Effect of diet composition on acid–base balance in adolescents, young adults and elderly at rest and during exercise
European Journal of Clinical Nutrition
The effects of 8 weeks of whey or rice protein supplementation on body composition and exercise performance
Could a vegetarian diet reduce exercise-induced oxidative stress? A review of the literature
Journal of Sports Sciences
The Best Athletes in Ancient Rome were Vegetarian!
Journal of Sport Science and Medicine
Nutritional considerations for vegetarian athletes
Physical fitness and vegetarian diets: is there a relation?
American Journal of Clinical Nutrition