SWAP-MEAT: Athlete Study

Study Aim

The goal of Stanford’s SWAP-MEAT: Athlete study is to explore the effect of three different diets on athletic performance. Participants enrolled in the study as runners or resistance trainers, but not both, and were asked to consume an animal meat diet, plant-based meat alternative diet, and a whole food plant-based diet for 4 weeks each. The primary outcome for runners was distance covered during a 12-minute timed run and 3-rep max exercises for resistance trainers. Secondary outcomes included VO2 max for runners and maximum push-ups and pull-ups for resistance trainers.

Eligible Participants

Eligible participants were required to meet the following criteria:

  • 18-35 years
  • Omnivorous
  • Recreational runner or recreational weight lifting for at least 1 year
  • Can maintain a consistent physical activity routine and exercise at least 3 days per week
  • Can consume ~2 servings/day of meat, plant-based meat alternatives, and whole food plant-based proteins

Study Design

If eligible, participants were asked to:

  • Complete physical activity logs and 3 days of diet tracking on a weekly basis
  • Complete an athletic field test (12 minute timed run or 3-rep maxes, push-ups, and pull-ups) at baseline and the end of each diet phase (Week 0, 4, 8, 12)
  • Rate perceived exertion, report weight and body fat percentage, and complete questionnaires after athletic field tests
  • Maintain a diet full of traditional meat products for 4 weeks, plant-based meat alternatives for 4 weeks, and whole food plant-based protein for 4 weeks



  • Participants learn how each diet affects their individual athletic performance, as well as that of the entire cohort
  • $100 provided per diet phase to support cooking and grocery shopping
  • Access support from the research team


In this study, runners and resistance trainers experienced no significant change in endurance or muscular strength on two predominately plant-based diets compared to an animal meat diet.

These findings suggest recreational athletes can maintain athletic performance on an omnivorous diet or a predominately plant-based diet.

The study results were published in the Nutrition Journal (https://pubmed.ncbi.nlm.nih.gov/36384651/) in November, 2022.