Beetroot Juice May Lower Perceived Exertion Without Boosting Swimming Speed
A recent systematic review and meta-analysis aimed to evaluate the potential benefits of beetroot juice (BRJ) or dietary nitrate supplementation on swimming performance. The study focused on understanding if these supplements could enhance performance, alter post-exercise blood lactate levels, and impact perceived exertion in swimmers.
The research synthesized data from existing studies and found that while prior research highlighted benefits in other sports, especially in running and cycling, the evidence for swimming-specific outcomes was limited. The comprehensive review incorporated randomized controlled trials and crossover studies that met specific criteria, including trials with placebo or no supplementation to compare outcomes.
Nine studies involving 120 swimmers were part of the quantitative meta-analysis, revealing no significant improvement in swimming performance when compared with placebo. However, a small but statistically significant reduction in perceived exertion was identified following supplementation, though results varied and the consistency of this effect is questionable.
Post-exercise blood lactate concentrations showed no meaningful difference between supplemented groups and placebo, suggesting no significant change in metabolic demands. The meta-analysis included trials across various swimming distances, yet no substantial performance gains were noted through supplementation.
The research highlighted methodological limitations such as small sample sizes and variability in study protocols, which may affect the generalizability of the findings. The overall certainty of evidence was rated low, partly due to biases and imprecision.
The authors concluded that, despite minor perceived exertion reductions, beetroot juice and nitrate supplements do not show a significant ergogenic benefit in swimming under the conditions studied. They emphasized the need for future research involving larger populations and controlled trial settings to further explore supplementation strategies and their potential impacts.
