Can recreational athletes thrive on a plant-based diet?
A new crossover study analysed the impact of 3 different diets on athletic performance.
12 runners and 12 resistance trainers – all eating an omnivorous diet and working out 3-4 times a week for at least a year – were randomly allocated to follow 3 dietary patterns for 4 weeks and then switch over without a washout period.
The 3 diets were as follows:
- WFPB (whole food plant-based, not vegan): a minimum of 2 meals consisting of whole grains, legumes, vegetables, fruits, nuts and seeds while minimising their consumption of processed foods, dairy products and eggs. Commonly consumed proteins were: quinoa, beans and tofu.
- PBMA (plant-based meat alternative protein): at least 2 servings of plant-based meat alternatives per day, commonly consumed protein sources were: Beyond Burger, Impossible Burger, and Gardein. The participants could have fish once a week.
- Animal: at least 2 servings of animal protein (mainly red meat and poultry) per day. In addition, they too had fish once a week.
The researchers measured the athletic performance of the participants at baseline and after each diet phase (at week 4, 8,12).
To test endurance, the runners completed the Cooper 12-minute timed run (distance covered in 12 minutes at maximum effort); VO2 max was also measured using Garmin watches.
Resistance trainers reported the number of push-ups and pull-ups on day one and performed a 3-max rep on machine-based exercises (chest press, leg press, lat pull-down) on day two.
The conclusion: no statistically significant difference in athletic performance on the 2 different diets! Body weight and body fat percentage was slightly lower on the two plant-based diets.
My take on this study:
- The participants were not vegan before the trial, nor were the diets they were assigned to 100% plant-based. There are two flaws with this: they were still consuming animal protein, even if only in small amounts; there may have been some residual effect of the animal protein they were consuming before the trial. The latter has been used as a limitation of other studies.
- Both the training logs and food tracking were self-reported which is always open to bias.
- There have been better studies analysing the effect of a 100% vegan diet on resistance training and endurance training, therefore I don’t feel this study offers any new information.
- Having said that, many hobby exercisers and recreational athletes are reluctant to replace their animal-based protein with plant proteins fearing a decline in their performance even though data suggests that reducing the intake of animal protein is essential in fighting climate change.
- I felt that this study hoped to reassure athletes that they can maintain their athletic performance with more more plant protein in their diet.
