Change in marker of hydration correspond to decrement in lower body power following basketball match

Background: Muscle damage and dehydration are common during basketball matches, but their relationship with performance in this sport is unclear. The aim of this study was to correlate changes in muscle damage (creatine kinase), hydration status (Na+; K+; body mass), and lower body power (countermovement jump) occurring in young athletes during a basketball competition. Methods: Fourteen basketball-players (age, 17.1 ± 3.4 years) simulates a 40-min match, with pre-post measurement conducted for creatine kinase, Na+, K+, body mass, and countermovement jump. Basketball-players were divided according to the magnitude of jump performance decrease after the match into: low decrease and high decrease. Results: creatine kinase and [Na +] increased (38.1% and 1.4%, respectively; P < 0.0001), while body mass and countermovement jump decreased (1.3% and 10.8%, respectively; P < 0.0002), without changes in [K +] after the match. Differences were found between low and high decrease groups in body mass loss (P = 0.03) and [Na +] changes (P = 0.02). No differences were found between groups in creatine kinase and [K +]. Countermovement jump reduction was associated to body mass loss (r = 0.63, P = 0.01) and [Na +] changes (r= −0.63, P = 0.02), not with creatine kinase or [K +] changes. Conclusion: These results reaffirm the notion that basketball matches induce muscle damage and dehydration. As a novelty, these results suggest that dehydration have a important role on reduced explosive performance during basketball competition and should be a key point in recovery strategies.