Mechanical, Metabolic and Perceptual Response during Sprint Training.

This study aimed to analyze perceptual, metabolic and mechanical responses to sprint training sessions. 9 male high-level sprinters performed 40 m running sprints up to a loss of 3% in speed, with 4 min rests between sets. Perceptual (rating of perceived exertion, RPE), mechanical (speed and countermovement jump height loss) and metabolic (blood lactate and ammonia) parameters were measured pre-exercise and after each sprint was performed. Relationships between the variables were calculated with a 90% confidence interval. Jump height loss showed almost perfect relationships with both blood lactate (r=0.96 (0.95 to 0.97)) and ammonia (r=0.95 (0.94 to 0.95)), whereas speed loss, number of sprints performed and RPE values showed large-very large relationships with blood lactate and ammonia. Furthermore, an almost perfect curvilinear relationship was observed between lactate and ammonia concentrations (R(2)=0.96 (0.95 to 0.97)). These results suggest that countermovement jump (CMJ) height can be used to quantify the fatigue induced during a typical sprint training session, and may prove a useful tool to facilitate individualized load monitoring. The results indicate that the CMJ is a better monitor of metabolic fatigue than traditional measures.