Effects of Phototherapy Associated With Sprint and Squat Training on Cardiac Autonomic Modulation: Randomized, Placebo-controlled Trial

Recent studies have shown positive results in the application of phototherapy for the improvement of performance and acceleration of the healing process of the body homeostasis. Among the methods used to assess the recovery post-exercise has cardiac autonomic modulation assessed by heart rate variability (HRV), a tool widely used in sports to evaluate medium global behavior of the autonomic nervous system. Objective: analyze and compare the effect of a special protocol of phototherapy using different light sources interacting with a combined training with an autonomic modulation of heart rate in different moments (baseline; tracking daily; recovery post-exercise and after training). Method: 45 male participants will be allocated from a stratified randomization into three groups: control (n=15), placebo (n=15) and group special protocol of phototherapy (n=15). Participants will perform a combined training of sprints and squats twice a week for twelve weeks divided into two phases. The application of phototherapy and placebo was administered in phase 2, after sprints and just before the squat. The phototherapy was used combine different light sources and wavelength (red and infrared). Was analyze HRV in five moments: baseline; traking daily; week target of phase I and II; after training. The weeks target consist of training sessions with greater energy expenditure (largest intensity). The sphericity of the data was tested by Mauchly test. In case of violation of the sphericity assumption, the correction of Greenhouse-Geisser was performed. The data was analyzed using analysis of variance for repeated measures (Bonferroni post-test), which provide information on the effects of time, group and interaction. All statistical analyzes assume the significance level of 5%.