LAUSR

PURPOSE Repeated-sprint training (RS) is commonly conducted in normoxia, but its completion with localized (blood flow restriction, BFR) or systemic hypoxia has proven effective for performance enhancement. Yet, few studies have applied these types of RS sessions in racket sports. We aimed to determine the acute responses to these types of training in elite badminton players. METHODS Eight male elite badminton players participated in this randomized, cross-over study. They performed three on-court RS sessions, each consisting of 3 sets of 10 repetitions of 10-s badminton-specific movements in normoxia (RSN), systemic normobaric hypoxia (RSH, FiO2=14%) or with BFR (RS-BFR, 40% arterial occlusion pressure). Performance, perceptual (i.e., rating of perceived exertion), and physiological (i.e., pulse saturation, muscle oxygenation, blood lactate, creatine kinase, heart rate variability) responses were measured after each set and up to 48 h post-session. RESULTS RS-BFR induced a greater performance impairment (lower distance and accelerations) and a higher local perceived exertion in the legs than RSN and RSH (p<0.05), whereas a greater overall fatigue was reported with RSH (p<0.05). RSH induced a lower saturation (p<0.001), but no differences were observed in muscle oxygenation between conditions. No differences in creatine kinase or heart rate variability were observed at any time point (from baseline up to 48 h after the session). CONCLUSIONS RS-BFR -and to a lower extent RSH- resulted in an impaired performance and a higher perceived strain than RSN. However, these two hypoxic methods seem not to induce a long-lasting (post 24-48 h) physiological stress in elite badminton players.