Background/Aims: Humans consuming a vegetarian diet have a reduced relative risk in coronary heart disease, hypertension, diabetes mellitus, obesity and some cancers. Regular physical activity also assists in preventing, and reducing the severity of these conditions. An association between these two factors is being acknowledged with athletes adapting their diet to optimise physical performance. This study aimed to examine the evidence for the relationship between consuming a predominately vegetarian diet and improved physical performance.
Methods: A systematic literature review was undertaken using the SCOPUS database. No date parameters were set. The keywords; vegetarian* OR vegan* AND sport* OR athlete* OR training OR performance OR endurance’ were used. Included studies; (i) directly compared a vegetarian based diet to an omnivorous/mixed diet, (ii) directly assessed physical performance, not biomarkers of physical performance, (iii) did not use supplementation emulating a vegetarian diet. Reference lists were hand searched for additional studies.
Results: Seven randomised controlled trials and one cross-sectional study met the inclusion criteria. No distinguished differences between vegetarian diets and omnivorous mixed diets were identified when physical performance was compared.
Conclusion: Limited evidence is available to determine if consuming a predominately vegetarian diet will impact performance in athletes. Further research is warranted though the limited studies of this review did show no impact.
Funding Source: N/A