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Carl M. Maresh, Lawrence E. Armstrong, Jay R. Hoffman, Daniel R. Hannon, Catherine L. V. Gabaree, Michael F. Bergeron, Michael J. Whittlesey and Michael R. Deschenes

In the present study, the effects of an increased daily dose of a dietary supplement (ATP-E, 0.2 g · kg1 · day1) on Wingate test performance were examined in 12 men (21 ± 1.6 years) prior to and following 14 days of supplement and placebo ingestion. A double-blind and counterbalanced design was used. Results revealed higher (p < .007) preexercise blood ATP (95.4 ± 10.5 μmol · dl1) for the entire group following 14 days of ATP-E ingestion compared to placebo measures (87.6 ± 10.9 μmol · dl1). Mean power (667 ± 73 W) was higher (p < .008) after 14 days of ATP-E ingestion versus placebo (619 ± 67 W). Peak plasma lactate was lower (p < .07) after 14 days of ATP-E ingestion (14.9 ± 2.8 mmol · L1) compared to placebo (16.3 ± 1.6 mmol · L1). These data suggested that the improvement in 30-s Wingate test performance in this group may be related to the increased dose of ATP-E.

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Jaci L. VanHeest, Jim Stoppani, Tim P. Scheett, Valerie Collins, Melissa Roti, Jeffrey Anderson, George J. Allen, Jay Hoffman, William J. Kraemer and Carl M. Maresh

Objective:

To determine the effects of Vicoprofen® and ibuprofen on aerobic performance, agility, and pain after exercise-induced muscle damage.

Design:

Double-blind randomized, placebo-controlled, repeated-dose clinical trial.

Setting:

Human-performance and sports-medicine laboratory.

Participants:

36 healthy men.

Methods and Measures:

Baseline testing was performed, 72 hours after which subjects performed eccentric exercise to induce muscle damage. They were evaluated for pain 24 hours postdamage and placed randomly into 3 groups: Vicoprofen (VIC), ibuprofen, or placebo (P). Postdamage testing was performed every day for 5 days. Subjects performed an economy run and a t-agility test to determine exercise performance.

Results:

The drugs had no significant effect on performance throughout the 5-day evaluation period. Pain was lower at days 4 and 5 in the VIC group than in P.

Conclusions:

It appears that Vicoprofen reduced pain after muscle damage, but the drug interventions did not enhance performance in aerobic and agility tasks.

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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.

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Carl M. Maresh, Catherine L. Gabaree, Jay R. Hoffman, Daniel R. Hannon, Michael R. Deschenes, Lawrence E. Armstrong, Avron Abraham, Frederick E. Bailey and William J. Kraemer

To examine the effect of a nutritional supplement (ATP-E™) on high intensity exercise performance, 23 physically active males volunteered to perform six Wingate Anaerobic Power tests. Tests were performed prior to and at 14 and 21 days during ATP-E~o~r placebo ingestion. f i e experiment followed a double-blind and random-order design. Twelve subjects (responders, R) showed an increase in preexercise blood ATP on Day 14 of ATP-E™ ingestion compared to control measures. The remaining 11 subjects (nonresponders, NR) had no change in pree~e~cibselo od ATP. Peak power and mean power were unchanged for both R and NR subjects across the exercise tests, but R experienced a decrease (p < 0.05) in immediate postexercise plasma lactate on Day 14 of ATP-E™ testing compared to their control measures. NR had no change in peak plasma lactate at any time during the study. The results suggest that short-term high intensity exercise performance was maintained in R with less reliance on anaerobic metabolism, and that response was evident following 14 days of ATP-E™ ingestion.

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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

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.

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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

Purpose:

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.

Methods:

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.

Results:

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).

Conclusions:

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.

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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

Objective:

To determine the effects of Vicoprofen®, ibuprofen, and placebo on anaerobic performance and pain relief after resistance-exercise-induced muscle damage.

De-sign:

Randomized, controlled clinical study.

Setting:

University human-performance/sports-medicine laboratory.

Participants:

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.

Results:

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.

Conclusions:

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.