This study examined the effect of a 10-week introductory judo course on postural control during a bilateral reactionary gripping task using different stance conditions. A total of 20 volunteers were divided into experimental (JDO) and control (CON) groups. Countermovement jump was measured and center of pressure variables were evaluated while performing a bilateral reactionary gripping task under different stance conditions during pre- and posttesting. No interactions were observed for the center of pressure variables (p > .05), while both countermovement jump power (+165.4 W; p = .036) and height (+3.5 cm; p = .018) significantly improved in the JDO group following the 10-week course. Results indicate that 10 weeks of an introductory judo course has no effect on postural control while performing a bilateral reactionary gripping task using different stance conditions.
Tyler W.D. Muddle, David H. Fukuda, Ran Wang, Joshua J. Riffe, David D. Church, Kyle S. Beyer, Jay R. Hoffman and Jeffrey R. Stout
Kyle S. Beyer, Jeffrey R. Stout, Michael J. Redd, Kayla M. Baker, Haley C. Bergstrom, Jay R. Hoffman and David H. Fukuda
Purpose: To examine the reliability and the maturity-related differences of fatigue thresholds (FTs) among youth males. Methods: Twenty-nine youth males (11–17 y) completed 2 ramp exercise tests on a cycle ergometer. Systemic FTs were calculated from gas exchange and ventilation variables. Localized FTs were calculated from electromyography and near-infrared spectroscopy of the vastus lateralis. All FTs were determined using the maximal distance method and expressed relative to maximal oxygen consumption. All participants were grouped according to the number of years from peak height velocity into PRE- (< −1.5 y), PERI- (−1.5 to +1.5 y) and POST- (> +1.5 y) peak height velocity. Reliability was assessed with intraclass correlation coefficients, and differences between groups were assessed with analysis of variance and Cohen’s d coefficients. Results: Analysis of variance revealed significant group differences with PRE having significantly greater systemic pulmonary FTs than POST, while localized muscular FTs were significantly greater in PRE when compared with PERI and POST. All FTs exhibited excellent reliability (intraclass correlation coefficient > .75) in all maturity groups. Conclusion: Maturity status appears to influence the onset of FTs among youth male athletes, with FTs occurring later in younger athletes. Furthermore, all FTs were reliable measures regardless of maturity.
William P. McCormack, Jay R. Hoffman, Gabriel J. Pruna, Tyler C. Scanlon, Jonathan D. Bohner, Jeremy R. Townsend, Adam R. Jajtner, Jeffrey R. Stout, Maren S. Fragala and David H. Fukuda
During the competitive soccer season, women’s intercollegiate matches are typically played on Friday evenings and Sunday afternoons. The efficacy of a 42-h recovery period is not well understood. This investigation was conducted to determine performance differences between Friday and Sunday matches during a competitive season.
Ten NCAA Division I female soccer players (20.5 ± 1.0 y, 166.6 ± 5.1 cm, 61.1 ± 5.8 kg) were monitored with 10-Hz GPS devices across 8 weekends with matches played on Friday evenings and Sunday afternoons. The players were outside backs, midfielders, and forwards. All players had to participate in a minimum of 45 min/match to be included in the study. Average minutes played, total distance covered, total distance of high-intensity running (HIR) (defined as running at a velocity equal to or exceeding 3.61 m/s for longer than 1 s), the number of HIR efforts, and the number of sprints were calculated for each match. Data for Friday vs Sunday matches were averaged and then compared using dependent t tests.
No differences were seen in minutes played, distance rate, or number of sprints between Friday and Sunday matches. A significant (P = .017) decrease in rate of HIR between Friday (25.37 ± 7.22 m/min) and Sunday matches (22.90 ± 5.70 m/min) was seen. In addition, there was a trend toward a difference (P = .073) in the number of efforts of HIR between Friday (138.41 ± 36.43) and Sunday (126.92 ± 31.31).
NCAA Division I female soccer players cover less distance of HIR in games played less than 48 h after another game. This could be due to various factors such as dehydration, glycogen depletion, or muscle damage.
William J. Kraemer, Ana L. Gómez, Nicholas A. Ratamess, Jay R. Hoffman, Jeff S. Volek, Martyn R. Rubin, Timothy P. Scheett, Michael R. McGuigan, Duncan French, Jaci L. VanHeest, Robbin B. Wickham, Brandon Doan, Scott A. Mazzetti, Robert U. Newton and Carl M. Maresh
To determine the effects of Vicoprofen®, ibuprofen, and placebo on anaerobic performance and pain relief after resistance-exercise-induced muscle damage.
Randomized, controlled clinical study.
University human-performance/sports-medicine laboratory.
36 healthy men.
Methods and Measures:
After baseline testing (72 h), participants performed an eccentric-exercise protocol. Each was evaluated for pain 24 h later and randomly assigned to a Vicoprofen (VIC), ibuprofen (IBU), or placebo (P) group. Postexercise testing was performed every 24 h for 4 d.
Significantly greater muscle force, power, and total work were observed in VIC than in P (P < .05) for most time points and for IBU at 48 h.
Anaerobic performance is enhanced with VIC, especially within the first 24 h after significant muscle-tissue damage. The greater performances observed at 48 h might be a result of less damage at this time point with VIC treatment.