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Bettina Karsten, Jonathan Baker, Fernando Naclerio, Andreas Klose, Antonino Bianco and Alfred Nimmerichter

Critical power (CP) is defined as the highest sustainable rate of aerobic metabolism without a continuous loss of homeostasis. 1 It separates power-output (PO) intensities, for which exercise tolerance is predictable (PO > CP), from those of longer sustainable durations (PO < CP). The second

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Michal Wilk, Michal Krzysztofik, Milosz Drozd and Adam Zajac

The ability to generate power is one of the most significant factors that determine performance in numerous sport disciplines. Power output can be described by the relationship between the force generated by the muscles and movement velocity. 1 Resistance training is one of the key tools used in

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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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Ryland Morgans, Rocco Di Michele and Barry Drust

indicative of the supercompensation that follows an exercise stimulus. 6 The quantification of jump performance at relevant times after matches may therefore provide a way to evidence the potential for match play to act as a training stimulus for muscle power in soccer players. Methods Fifteen male

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Todd C. Pataky, Greg P. Slota, Mark L. Latash and Vladimir M. Zatsiorsky

During power grasp, the number of local force maxima reflects either the central nervous system’s preferential use of particular hand regions, or anatomical constraints, or both. Previously, both bimodal and trimodal force maxima have been hypothesized for power grasp of a cylindrical handle. Here we measure the number of local force maxima, with a resolution of 4.8°, when performing pushing and pulling efforts in the plane perpendicular to the cylinder’s long axis. Twelve participants produced external forces to eight targets. The number of contacts was defined as the number of local maxima exceeding background variance. A minimum of four and a maximum of five discrete contacts were observed in all subjects at the distal phalanges and metacarpal heads. We thus reject previous hypotheses of bimodal or trimodal force control for cylindrical power grasping. Since we presently observed only 4–5 contacts, which is rather low considering the hand’s kinematic flexibility in the flexion plane, we also reject hypotheses of continuous contact, which are inherent to current grasping taxonomy. A modification to current grasping taxonomy is proposed wherein power grasp contains separate branches for continuous and discrete contacts, and where power and precision grasps are distinguished only by grasp manipulability.

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Anni Vanhatalo, Andrew M. Jones and Mark Burnley

The critical power (CP) is mathematically defined as the power-asymptote of the hyperbolic relationship between power output and time-to-exhaustion. Physiologically, the CP represents the boundary between the steady-state and nonsteady state exercise intensity domains and therefore may provide a more meaningful index of performance than other well-known landmarks of aerobic fitness such as the lactate threshold and the maximal O2 uptake. Despite the potential importance to sports performance, the CP is often misinterpreted as a purely mathematical construct which lacks physiological meaning and only in recent years has this concept begun to emerge as valid and useful technique for monitoring endurance fitness. This commentary defines the basic principles of the CP concept, outlines its importance to high-intensity exercise performance, and provides an overview of the current methods available for its assessment. Interventions including training, pacing and prior exercise can be used to alter the parameters of the power-time relationship. A future challenge lies in optimizing such interventions in order to positively affect the parameters of the power-time relationship and thereby enhance sports performance in specific events.

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Karin Roeleveld, Eric Lute, Dirkjan Veeger, Luc van der Woude and Tom Gwinn

To assess power output, force application, and kinematics of wheelchair propulsion in peak exercise, nine wheelchair athletes with medical lesion levels of T8 or lower performed a 30-s sprint test on a stationary wheelchair ergometer. Mean power output, calculated for the right wheel only, was 59.4 ± 8.5 W. The ratio between effective force and total propulsive force was 60 ± 6%. A negative torque around the hand and a not tangentially directed total force accounted for this low effectiveness. Since the subject group was highly trained, their technique was considered to be optimal for the given circumstances. Therefore, athletes who want to improve power output by increasing effectiveness should keep in mind the existence of a nontangential propulsive force and a braking torque applied by the hands onto the hand rim surface. It is likely that both aspects will be influenced by the geometry of the wheelchair, for example, hand rim dimension or seat position.

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Terry J. Housh, Glen O. Johnson and Dona J. Housh

The purpose of this investigation was to examine age related changes in muscular power of high school wrestlers. A total of 155 high school wrestlers (M age±SD = 16.5±2.4 yrs) volunteered as subjects for this investigation. The sample included only wrestlers who were ≤ 16.00 years (younger group, n=75) or >17.00 years (older group, n=80). All subjects completed a Wingate anaerobic test to determine mean (MP) and peak (PP) power as well as underwater weighing for body composition assessment. The results indicated significant (p<0.05) group differences for absolute MP and PP but no differences when adjusted for BW and FFW. Thus the enhanced muscular power in the older group of high school wrestlers was associated with increases in BW and FFW.

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Laura K. Fewell, Riley Nickols, Amanda Schlitzer Tierney and Cheri A. Levinson

heart beats per minute. The CSCS then used the following equations to calculate patients’ VO 2 max scores: VO 2 max = 111.33 − (0.42 × HR) for males; VO 2 max = 65.81 − (0.1847 × HR) for females. Vertical jump was utilized to assess patients’ power output and was measured at the treatment center using

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Seihati A. Shiroma, Ursula F. Julio and Emerson Franchini

supplementary aerobic training program, judo athletes presented faster V ˙ O 2 recovery after a maximal graded exercise test (GET) and faster heart rate (HR) recovery after a high-intensity judo-specific test. 8 Thus, aerobic power development has been associated with faster creatine phosphate resynthesis