Plant-based diet matched omnivore diet for recreational athletes in Rutgers performance study

Recreational athletes maintained their endurance and strength after switching from an omnivore diet to a plant-based diet for four weeks, according to a new study led by researchers from Rutgers University and several partner institutions.

• Researchers found no statistically significant differences in running endurance or strength after recreational athletes completed four weeks on plant-based and omnivore diets.
• Participants consumed less protein on the plant-based diet but still met published recommendations for general fitness activities while increasing their intake of fiber, iron and calcium.
• The researchers said the findings applied to healthy recreational college athletes over a short period and called for larger, longer-term studies.

The study, published in Nutrition Journal, examined whether recreational runners and resistance trainers could maintain athletic performance after replacing meat with plant-based protein sources. The research addressed growing interest in plant-based eating among athletes, as well as widespread claims on social media that avoiding meat compromises exercise performance.

Researchers recruited 36 undergraduate students from Rutgers University, Stanford University, Vanderbilt University and the University of Reading in the UK. The group included 16 recreational runners and 20 resistance trainers who exercised three or four times a week.

Participants completed two four-week dietary phases. During one phase they followed an omnivore diet, consuming at least two servings of animal protein daily. During the other, they replaced those servings with plant-based proteins such as beans, tofu or plant-based meat alternatives. The order was randomized, allowing each participant to act as their own control.

Peggy Policastro, Rutgers' Director of Behavioral Nutrition and a registered dietitian, said the study aimed to answer a question becoming increasingly relevant as more athletes considered reducing their meat consumption.

"The researchers wanted to solve a puzzle regarding whether switching from a meat-inclusive diet to a plant-based diet hurts an athlete's physical performance," said Policastro.

She added that misinformation surrounding plant-based diets had become widespread.

"Popular social media claims frequently spread misinformation that plant-based diets fail to provide enough calories or protein to meet the demands of exercise," said Policastro. "The study specifically sought to test these claims by examining recreational student athletes who rely on university dining halls for most of their daily meals."

Participants were asked to maintain their normal exercise routines while recording their food intake at least three days each week. Performance testing took place before the study and after each dietary phase.

Runners completed a 12-minute endurance test, while resistance trainers performed three-repetition maximum tests on the chest press, lat pulldown and leg press.

The results showed only minor differences between the two diets.

During the omnivore phase, runners averaged 8,720 feet (2,658 meters) in the 12-minute test, compared with 8,602 feet (2,622 meters) during the plant-based phase. Resistance trainers recorded combined strength scores around 4% lower during the plant-based phase.

Neither difference reached statistical significance.

"After four weeks on each diet, there were no statistically significant differences in athletic performance between the plant-based and omnivore phases," Policastro said. "Runners achieved similar distances in their timed runs, and weightlifters maintained virtually the same maximum strength across chest, back and leg press exercises regardless of the diet they were following."

Although participants consumed substantially less protein during the plant-based phase, their intake remained within published recommendations for people participating in general fitness activities.

Average daily protein intake fell from 103 grams on the omnivore diet to 71 grams on the plant-based diet. However, reported calorie intake remained similar throughout both phases.

Researchers also identified nutritional differences between the diets. The plant-based meals provided more carbohydrates, fiber, iron and calcium, while the omnivore diet contained higher amounts of saturated fat, cholesterol and vitamin B12.

The authors said these findings highlighted the importance of planning balanced diets, particularly because people following fully plant-based diets for extended periods often require vitamin B12 supplementation.

The research formed part of the Menus of Change University Research Collaborative, an international partnership that uses university dining halls to study eating habits while encouraging healthier and more sustainable food choices.

Rutgers coauthor Alyssa Guidetti recruited participants from the university and analyzed the Rutgers data under Policastro's supervision.

"She worked on this study as an undergraduate and then continued exploring the same topic through a systematic review for her master's," Policastro said.

Guidetti now works as a sports dietitian for Rutgers Athletics.

Beyond measuring performance, the researchers also collected feedback on participants' experiences with plant-based eating.

Many students suggested that university dining services could improve both the taste and variety of plant-based meals. Several participants preferred minimally processed foods such as beans and tofu over processed meat alternatives, while cultural background, familiarity, cost and accessibility all influenced meal choices.

The researchers cautioned that the findings should not be generalized beyond the study population.

The trial focused on healthy recreational college athletes over just eight weeks, and reported calorie intake appeared unusually low, suggesting some food consumption may not have been recorded. As a result, the study could not determine how plant-based diets might influence elite athletes or affect performance, muscle growth and recovery over longer periods.

Policastro also noted that the research did not prove the two diets produced identical outcomes, only that the observed differences were not statistically significant within this study.

She said larger studies with longer follow-up periods and tighter dietary controls would be needed to provide more definitive answers.

Even so, she said the results should give confidence to physically active students interested in eating more plant-based foods.

"This is important because it shows that everyday athletes can safely choose plant-based foods without worrying about harming their fitness or strength goals," Policastro said. "These findings provide evidence-based support for colleges to comfortably expand healthy and environmentally friendly plant-based menu options for their active student populations."

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