Effect of photobiomodulation on maximal lactate production rate on swimmers: a randomized, crossover, double-blind and placebo-controlled study

Aim: This study aimed to verify the acute effect of photobiomodulation (PBM) on maximal lactate production rate (VLamax) in front crawl swimmers. Methods: Fifteen male swimmers (20.9 ± 2.4-year-old) participated this study. Three sets crawls were performed at distances 100-, 200- and 400-m under three experimental conditions: PBM (420 J), placebo (PLA) control (C) randomized, crossover, double-blind placebo-controlled or PLA applied simulated before performance tests. One-way Anova for repeated measurements used statistical analyses. Results: The results showed that prior application did not affect VLamax swimmers: 100-m (PBM = 0.20 0.05 mmol·L-1·s-1; 0.04 mmol·L-1·s-1 C 0.21 0.04; mmol·L-1·s-1); 200-m 0.09 0.03 0.08 0.02 mmol·L-1·s-1) 0.01 mmol·L-1·s-1). Nor swim time (ST) performance: ST 100 m 65.5 6.3 s; 65.2 5.6 66.0 5.9 s); 200 148.5 17.9 149.4 16.4 150.1 400 327.7 38.2 321.6 47.7 329.5 41.2 s). Conclusions: swimming tests significantly modify covering 400-m.