Capacitive Resistive Electric Transfer Therapy on Muscle Recovery

This study aims to evaluate the effectiveness of Capacitive Resistive Electric Transfer (CRET) therapy combined with post-competition massage in the recovery and muscle function of professional athletes. It is designed as a randomized, double-blind, crossover clinical trial. The primary objective is to analyze the efficacy of this combined protocol in muscle recovery after performing the Wingate anaerobic power and capacity test. Secondary objectives include assessing changes in muscle fatigue, muscle function of the rectus femoris and vastus lateralis, physiological changes in blood lactate concentration and oxygen saturation, and intramuscular structural changes through ultrasound before and after the intervention. The study will recruit professional athletes from disciplines that require anaerobic muscle metabolism, such as cycling, athletics, triathlon, CrossFit, and duathlon. Participants must be federated athletes who train at least four times per week and actively compete at regional, national, or international levels. Exclusion criteria include recent sports injuries preventing test performance, prior exposure to CRET therapy, allergies to conductive gel, language barriers, participation in other research studies, or ongoing pharmacological treatment that could interfere with measurements. Participants will attend four study sessions, divided into two sets of two consecutive days. On the first day, they will perform the Wingate test followed by the assigned post-competition massage with either CRET therapy or a placebo intervention. On the second day, they will repeat the Wingate test. After a three-week washout period, participants will switch to the opposite group. The intervention group will receive a 60-minute CRET therapy session with both resistive and capacitive modes applied at different power intensities, combined with a standardized recovery massage. The placebo group will receive the same massage while undergoing a simulated CRET therapy, with t