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Sandro Venier, Jozo Grgic and Pavle Mikulic

flexion strength and power, (3) barbell velocity in resistance exercise, and (4) whole-body power output. We hypothesized that caffeine in this form would elicit an ergogenic effect in all explored aspects of exercise performance. Methods Experimental Design This study employed a randomized, cross

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Dajo Sanders, Mathieu Heijboer, Ibrahim Akubat, Kenneth Meijer and Matthijs K. Hesselink

Purpose:

To assess if short-duration (5 to ~300 s) high-power performance can accurately be predicted using the anaerobic power reserve (APR) model in professional cyclists.

Methods:

Data from 4 professional cyclists from a World Tour cycling team were used. Using the maximal aerobic power, sprint peak power output, and an exponential constant describing the decrement in power over time, a power-duration relationship was established for each participant. To test the predictive accuracy of the model, several all-out field trials of different durations were performed by each cyclist. The power output achieved during the all-out trials was compared with the predicted power output by the APR model.

Results:

The power output predicted by the model showed very large to nearly perfect correlations to the actual power output obtained during the all-out trials for each cyclist (r = .88 ± .21, .92 ± .17, .95 ± .13, and .97 ± .09). Power output during the all-out trials remained within an average of 6.6% (53 W) of the predicted power output by the model.

Conclusions:

This preliminary pilot study presents 4 case studies on the applicability of the APR model in professional cyclists using a field-based approach. The decrement in all-out performance during high-intensity exercise seems to conform to a general relationship with a single exponential-decay model describing the decrement in power vs increasing duration. These results are in line with previous studies using the APR model to predict performance during brief all-out trials. Future research should evaluate the APR model with a larger sample size of elite cyclists.

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Gemma N. Parry, Lee C. Herrington and Ian G. Horsley

Upper-limb muscular power output is a fundamental and highly desirable characteristic across a number of explosive short-duration sports. 1 , 2 Because upper-limb muscle power output is considered to be a principle movement skill and a key aspect of sporting performance and athletic ability, it is

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M. Travis Byrd, Jonathan Robert Switalla, Joel E. Eastman, Brian J. Wallace, Jody L. Clasey and Haley C. Bergstrom

The critical-power (CP) (and critical force) test of Monod and Scherrer involved dynamic, intermittent, static, and continuous muscle actions for isolated movements of synergic muscle groups including the forearm flexors, forearm extensors, and leg flexors. 1 This test involves local muscle work

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Mário A.M. Simim, Gustavo R. da Mota, Moacir Marocolo, Bruno V.C. da Silva, Marco Túlio de Mello and Paul S. Bradley

their physical capacity, it is very difficult to objectively verify fatigue using time-motion analysis alone. Fatigue in AS might also be highly complex, and thus, time-motion characteristics and game-induced decrements in neuromuscular measures (i.e., muscular endurance and power) must also be

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Taylor K. Dinyer, M. Travis Byrd, Ashley N. Vesotsky, Pasquale J. Succi and Haley C. Bergstrom

The critical power (CP) model was originally developed as a 2-parameter linear model to examine the relationship between total work and time to exhaustion ( T lim ) for dynamic, continuous isometric, and intermittent isometric contractions of a muscle or local muscle group (less than one-third the

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Nicholas Burton and Cheri Bradish

power in ambush-marketing ethics. In so doing, the study takes a historical perspective on the IOC’s rights-management efforts and the ethical framing of ambush marketing as part of a broader communication strategy intended to inform consumer opinion. Note that this research builds on and extends Ellis

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Brian A. Eiler, Rosemary Al-Kire, Patrick C. Doyle and Heidi A. Wayment

surprising given that sexual violence is often committed by individuals in positions of power and authority across a wide variety of contexts (e.g.,  Brackenridge, 2001 ; Watts & Zimmerman, 2002 ). Unfortunately, literature on athletes’ psychosocial experiences and reactions to abuse (e

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Aitor Iturricastillo, Cristina Granados, Raúl Reina, José Manuel Sarabia, Ander Romarate and Javier Yanci

them at any time of the season to assess the physical fitness of the players and the evolution of these abilities. Wheelchair sports, including WB, depend on the ability to generate strength and power with the upper extremities, 9 which especially influence wheelchair handling and propulsion. 10

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Erin E. Sutton, M. Regina Coll and Patricia A. Deuster

Acute tyrosine ingestion is thought to improve aerobic endurance, muscle strength and endurance, and anaerobic power of men undergoing severe physiologic stress. In a double-blind, crossover study, 20 men (32 ± 1 y old) underwent 2 loadcarriage treadmill sessions, 1 after taking tyrosine (150 mg/kg L-crystalline tyrosine) and 1 after taking placebo. Tyrosine dosage was based on subject weight and ingested 30 min before load carriage. A physical performance battery was administered after the load carriage: maximal and submaximal handgrip, pull-ups, and stair stepping with weight. Total time on treadmill was not significantly lengthened with ingestion of tyrosine (118.9 ± 1.4 min) as compared with placebo (119.2 ± 1.2 min). Total power for stair stepping (tyrosine 223 ± 8 watts, placebo 216 ± 9 watts) and muscle strength and endurance (handgrip) was not significantly improved by tyrosine ingestion. The results indicate that acute ingestion of tyrosine by healthy men has no measurable effect on endurance, muscle strength, or anaerobic power.