Is plant-based nutrition favorable to athletic performance?
A recent published scientific paper has looked to address this question through a study looking at 28 recreational female vegan runners comparing measures of endurance and strength performance against a matched group of meat-eating counterparts. Up to now the scientific literature has been equivocal with regards to performance with reviews suggesting, partly due to the lack of studies, that there is no detriment or improvement in performance.
Some athletes have still adopted a vegetarian/vegan diet, however, with a view to achieving improved performance through optimising carbohydrate intake, weight management and other performance enhancements. It has been suggested that a vegan diet may improve performance through,
- Improved glycogen stores from increased carbohydrate intake,
- Improved immunity and reduction in oxidative stress through increased intake of phytochemicals and antioxidants and
- Reduced intramuscular acidity which can limit exercise performance.
Historically there have been very few studies, however, that have considered the effect of vegetarian or vegan diets on athletic performance. A recent review of the studies which have been undertaken comparing vegetarian and omnivorous nutrition and effects on physical performance concluded that a vegetarian diet neither hinders or improves performance, although only one study used a vegetarian diet adopted over an extended period of time, which would be the norm in a vegetarian athlete. These findings are in line with an earlier review which again showed neither a beneficial nor detrimental effect on performance of vegetarian diets.
Up until now the research into the effects of a vegan diet on performance have been virtually non-existent, however, and there may be some merit to the diet increasing performance due to the factors mentioned above but no evidence.
SO, WHAT DID THE RECENT STUDY SHOW?
The study suggests that a vegan diet does not seem to be harmful to endurance and strength performance, in healthy young lean women. In fact, it goes further and suggests that endurance might be better in vegans compared with omnivores. An earlier study into a group of elite male and female vegetarian athletes drew similar conclusions. Both studies suggest that the improved performance could well be down to the increased carbohydrate intake in the vegan participants. Total carbohydrate intake (303.4g) percentage intake (59%) and relative intake (5.1g/kg body weight) were much closer to recommended intakes for endurance athletes than those of the omnivorous participants with total carbohydrate at (225.4g) percentage intake (46%) and relative intake (3.7g/kg body weight). They also suggest that favorable oxidative stress and inﬂammation proﬁles may also be a factor in the performance benefits of the vegan diet.
This is encouraging, and logical given the higher carbohydrate intakes, and hopefully a sign that this is an area of scientific research gaining in interest. The more scientific evidence produced to support what has been mostly anecdotal evidence to date, the more credible the promotion of a vegan diet to support athletic training at all levels will be.
The bottom line is that the studies which have been undertaken suggest that a well-planned vegan diet can adequately support overall athletic performance and even improve endurance performance, while offering added health, environmental and ethical benefits.
Author: Philip Woodbridge
Philip Woodbridge is a registered Sports Nutritionist with the SENr (Sports and Exercise Nutrition Register) and specialises in plant-based nutrition through his consultancy P4S Nutrition. Philip is author of a nutrition guide and cookbook Plant-Based 4 Running.
Is a Vegan Diet Detrimental to Endurance and Muscle Strength?
All other scientific references for the above article can be found in the Plant-Based 4 Running cookbook and nutrition guide.