This study provides the largest and most geographically representative sex-specific and age-specific European normative values for children and adolescents, which have utility for health and fitness screening, profiling, monitoring and surveillance.

No abstract

Bloms, LP, Fitzgerald, JS, Short, MW, and Whitehead, JR. The effects of caffeine on vertical jump height and execution in collegiate athletes. J Strength Cond Res 30(7): 1855-1861, 2016-Caffeine ingestion elicits a variety of physiological effects that may be beneficial to maximal-intensity exercise performance, although its effectiveness and physical mechanism of action enhancing ballistic task performance are unclear. The purpose of this study was to examine the effects of caffeine ingestion on vertical jump height and jump execution in Division I collegiate athletes. The study used a single-blind, randomized, crossover design. Athletes (n = 25) consumed either caffeine (5 mg·kg) or placebo. After a 60-minute waiting period, athletes performed 3 squat jumps (SJ) and 3 countermovement jumps (CMJ) while standing on a force platform. Jump height and execution variables were calculated from mechanography data. In comparison with placebo, caffeine increased SJ height (32.8 ± 6.2 vs. 34.5 ± 6.7 cm; p = 0.001) and CMJ height (36.4 ± 6.9 vs. 37.9 ± 7.4 cm; p = 0.001). Peak force (p = 0.032) and average rate of force development (p = 0.037) were increased during the CMJ in the caffeine trail compared with the control. Time to half peak force was the only execution variable improved with caffeine (p = 0.019) during the SJ. It seems that caffeine affects both height and execution of jumping. Our data indicate that the physical mechanism of jump enhancement is increased peak force production or rate of force development during jumping depending on technique. The physical mechanism of jump enhancement suggests that the ergogenic effects of caffeine may transfer to other ballistic tasks involving the lower-body musculature in collegiate athletes.

No abstract

Current research has found conflicting results regarding the relationship between maximal oxygen uptake ((Equation is included in full-text article.)) and the repeated sprint ability (RSA) of hockey players. The purpose of this study was to use sport-specific testing methods to investigate this relationship. Forty-five (range, 18-24) college hockey players completed a graded exercise test on a skating treadmill to ascertain their (Equation is included in full-text article.). An on-ice repeated shift test was then conducted to evaluate each player's susceptibility to fatigue. First gate, second gate, and total test times were collected on the course and then used to calculate associated decrement scores. Second gate decrement was significantly correlated to (Equation is included in full-text article.)(r = -0.31, p = 0.04). Final stage completed during the graded exercise test was also significantly correlated to second gate and total decrement (r = -0.46, p = 0.001; r = -0.32, p = 0.03). No significant correlation was found between either first gate or total decrement score and (Equation is included in full-text article.)(r = -0.11, p = 0.46; r = -0.17, p = 0.26). The results of this study indicate that RSA is associated with (Equation is included in full-text article.)and final stage completed when using sport-specific testing methods.