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Effects of Caffeine on Exertion, Skill Performance and Physicality in Ice Hockey.

PURPOSE
The aim of this study was to determine the effects of low dose caffeine supplementation (3 mg/kg/BM) consumed one hour before the experiment on rating of perceived exertion (RPE), skills performance, and physicality in male collegiate ice hockey players.


METHODS
Using a double-blind, placebo-controlled, randomized cross-over experimental design, 15 collegiate ice hockey players participated in skills performance trials and 14 participated in scrimmage trials on a total of four days, with prescribed ice hockey tasks occurring following a one-hour high-intensity practice. In the skills performance trials, time to complete and error rate for each drill of the validated Western Hockey League (WHL) Combines Testing Standard was recorded. Peak head accelerations, trunk contacts and offensive performance were quantified during the scrimmage trials using accelerometery and video analysis. RPE was assessed in both the skills performance and scrimmage trials.


RESULTS
RPE was significantly greater in the caffeine (11.3 ± 2.0) vs. placebo (9.9 ± 1.9) condition post-practice (p=.002), with a trend toward greater RPE in caffeine (16.9 ± 1.8) vs. placebo (15.7 ± 2.8) post-scrimmage (p=.050). There was a greater number of peak head accelerations in the caffeine (4.35 ± 0.24) vs. placebo (4.14 ± 0.24) conditions (p=.028). Performance times, error rate, and RPE were not different between intervention conditions during the skills performance trials (p>.050).


CONCLUSIONS
A low dose of caffeine has limited impact on sport-specific skill performance and RPE but may enhance physicality during ice hockey scrimmages.