Evaluation of Skating Top Speed, Acceleration, and Multiple Repeated Sprint Speed Ice Hockey Performance Tests.

Bond, CW, Bennett, TW, and Noonan, BC. Evaluation of skating top speed, acceleration, and multiple repeated sprint speed ice hockey performance tests. J Strength Cond Res 32(8): 2273-2283, 2018-Skating speed, acceleration (ACC), and economy are important attributes related to ice hockey success and should ideally be tested on the ice in a reliable and time efficient manner that is accessible to coaches at all levels of the sport. The purpose of this study was to determine the reliability of certain on-ice tests and further, to use these results to evaluate changes in performance across a season. It was hypothesized that the tests' reliability would be excellent and that players would demonstrate improvements in performance associated with enhanced physiological conditioning. Forty male ice hockey players (16.2 ± 0.8 years, 1.76 ± 0.06 m, 73.7 ± 9.8 kg) completed top speed (TS), ACC, and multiple repeated sprint time (MRST) tests twice in the preseason (PRE 1 and 2) 1 week apart to examine reliability and once postseason (POST) to examine changes across the season. A high-speed video camera was used to time each test. The TS, ACC, and MRST demonstrated excellent within- and between-day reliability (interclass correlation coefficient [ICC] ≥ 0.83, typical error [TE] ≤ 2.6%) as well as within- and between-rater reliability (ICC ≥ 0.86, TE ≤ 0.5%). The team's TS and ACC were similar at all 3 assessments (p > 0.05), whereas MRST was faster at POST than at PRE 1 (p < 0.05). This test battery is reliable, time efficient, and inexpensive. All 3 tests may be used in team selection and identification of fatigue or overtraining. The MRST may be the most sensitive to short-term improvements related to ice hockey conditioning.

Endothelial, Cardiovascular, and Performance Responses to L-Arginine Intake and Resistance Exercise.

The purpose of this study was to examine the acute endothelial, cardiovascular, and performance responses to L-arginine intake by assessing flow-mediated dilation (FMD) and various indicators (e.g., heart rate, heart rate variability (HRV), blood pressure, torque) both before and after resistance exercise. Thirty (15 male, 15 female) physically active participants (mean ± SD: age 20.4 ± 1.8 years, height 176.9 ± 10.2 cm, body mass 76.0 ± 12.2 kg) volunteered for a randomized, cross-over, double-blind, placebo-controlled clinical trial. Participants completed five sets of elbow extension-flexion exercise after consumption of either 3 g L-arginine or 3 g of placebo. There was a significant decline in post-exercise elbow extension (p = 0.014) and flexion peak torque (p < 0.001). FMD response after exercise was ~5.8% less than before resistance exercise (L-arginine and placebo data pooled, p < 0.001). Baseline brachial artery diameter significantly increased post-FMD (p < 0.001), post-resistance exercise (p < 0.001), and post-resistance exercise FMD (p < 0.001). There were significant time effects for HRV when expressed as the square root of the mean of the sum of squares of differences between adjacent RR intervals (RMSSD) or the proportion of differences between adjacent normal (NN) RR intervals that exceed 50 ms (pNN50) (all p-values < 0.05), but there were no treatment or interaction effects (all p-values > 0.05). We conclude the increased vasodilation due to acute resistance exercise was not enhanced by acute supplementation with L-arginine nor was exercise performance augmented. Further, the relative contribution of sympathetic nervous system input increased with resistance exercise but was not influenced by the addition of L-arginine.