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Rafael E.A. Muchaxo, Sonja de Groot, Lucas H.V. van der Woude, Thomas W.J. Janssen and Carla Nooijen

handcycling race performance, expressed by average time-trial velocity, and when corrected for possible differences in classes regarding event distance, gender, and age, it would show an increase in average velocity from the lower to the higher classes. Methods Data Collection Publicly available official

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Alejandro Pérez-Castilla, Ainara Jiménez-Alonso, Mar Cepero, Sergio Miras-Moreno, F. Javier Rojas and Amador García-Ramos

received velocity performance feedback after the first half of repetitions of each set. (c) Im KR: participants received velocity performance feedback immediately after each repetition. (d) Avg KR: participants received feedback about the average velocity of each set. The peak concentric velocity (PCV) was

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Sarah J. Wherry, Cheryl Der Ananian and Pamela D. Swan

trials. Variables analyzed from the force plate were mediolateral maximum velocity (mm/s); anteroposterior maximum velocity (mm/s); average velocity/resultant velocity (mm/s); 95% of the total sway area ellipsis (95% area, mm 2 ); 66% of the total sway area (area effective, mm 2 ); and the length of the

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Rachel M. Koldenhoven, Kelly Martin, Abbis H. Jaffri, Susan Saliba and Jay Hertel

), SD of Gaze Deviation, and Average Velocities (in Meters per Second) in the X and Y Directions During 3 Target Conditions for Healthy and CAI Participants Variable No target Fixed target Moving target Healthy CAI Effect size (90% CI) Healthy CAI Effect size (90% CI) Healthy CAI Effect size (90% CI

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Wojciech Jedziniak, Piotr Lesiakowski and Teresa Zwierko

squared), saccade peak deceleration (in degrees per second squared), and saccade average velocity (in degrees per second). The ocular mobility index (%) was calculated using the formula 100 × (saccade duration/[fixation duration + saccade duration]), according to Poiroux et al. ( 2015 ). The Kolmogorov

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Sergio Jiménez-Rubio, Archit Navandar, Jesús Rivilla-García, Víctor Paredes-Hernández and Miguel-Ángel Gómez-Ruano

high-velocity profiles mentioned previously, along with the peak and average velocities of the soccer players, could indicate the load on the hamstring muscle complex. A comparison of these parameters before and after an injury could be used to determine the success of the return-to-play (RTP) process

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Luis Mochizuki, Marcos Duarte, Alberto Carlos Amadio, Vladimir M. Zatsiorsky and Mark L. Latash

We investigated changes in postural sway and its fractions associated with manipulations of the dimensions of the support area. Nine healthy adults stood as quietly as possible, with their eyes open, on a force plate as well as on 5 boards with reduced support area. The center of pressure (COP) trajectory was computed and decomposed into rambling (Rm) and trembling (Tr) trajectories. Sway components were quantified using RMS (root mean square) value, average velocity, and sway area. During standing on the force plate, the RMS was larger for the anterior-posterior (AP) sway components than for the mediolateral (ML) components. During standing on boards with reduced support area, sway increased in both directions. The increase was more pronounced when standing on boards with a smaller support area. Changes in the larger dimension of the support area also affected sway, but not as much as changes in the smaller dimension. ML instability had larger effects on indices of sway compared to AP instability. The average velocity of Rm was larger while the average velocity of Tr was smaller in the AP direction vs. the ML direction. The findings can be interpreted within the hypothesis of an active search function of postural sway. During standing on boards with reduced support area, increased sway may by itself lead to loss of balance. The findings also corroborate the hypothesis of Duarte and Zatsiorsky that Rm and Tr reveal different postural control mechanisms.

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Christian Lorenzen, Morgan D. Williams, Paul S. Turk, Daniel L. Meehan and Daniel J. Cicioni Kolsky

Purpose:

Running velocity reached at maximal oxygen uptake (vVO2max) can be a useful measure to prescribe training intensity for aerobic conditioning. Obtaining it in the laboratory is often not practical, and average velocities from time trials are an attractive alternative. To date, the efficacies of such practices for team sport players are unknown. This study aimed to assess the relationship between vVO2max obtained in the laboratory against two time-trial estimates (1500 m and 3200 m).

Methods:

During the early preseason, elite Australian Rules football players (n = 23, 22.7 ± 3.4 y, 187.7 ± 8.2 cm, 75.5 ± 9.2 kg) participated in a laboratory test on a motorized treadmill and two outdoor time trials.

Results:

Based on average velocity the 1500-m time-trial performance (5.01 ± 0.23 m·s−1) overestimated (0.36 m·s−1, d = 1.75), whereas the 3200-m time trial (4.47 ± 0.23 m·s−1) underestimated (0.17 m·s−1, d = 0.83) the laboratory vVO2max (4.64 ± 0.18 m·s−1). Despite these differences, both 1500-m and 3200-m time-trial performances correlated with the laboratory measure (r = -0.791; r = -0.793 respectively). Both subsequent linear regressions were of good ft and predicted the laboratory measure within ± 0.12 m·s−1.

Conclusion:

Estimates of vVO2max should not be used interchangeably, nor should they replace the laboratory measure. When laboratory testing is not accessible for team sports players, prescription of training intensity may be more accurately estimated from linear regression based on either 1500-m or 3200-m time-trial performance than from the corresponding average velocity.

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Miroslav Janura, Lee Cabell, Milan Elfmark and František Vaverka

The athlete’s inrun position affects the outcome for take-off in ski jumping. The purpose of this study was to examine the kinematic parameters between skiers’ adjacent body segments during their first straight path of the inrun. Elite ski jumpers participated in the study at the World Cup events in Innsbruck, Austria, during the years 1992 through 2001. A video image was taken at a right angle to the tracks of the K-110 (meter) jumping hill. Kinematic data were collected from the lower extremities and trunk of the athletes. Findings indicated that jumpers had diminished ankle and knee joint angles and increased trunk and hip angles over the 10 years. In recent years, the best athletes achieved a further length of their jumps, while they experienced slower inrun average velocity. These results are perhaps explained by several possible contributing factors, such as new technique of the jumper’s body kinematics, advancements in equipment technology, and somatotype of the jumpers.

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Robert U. Newton, William J. Kraemer, Keijo Häkkinen, Brendan J. Humphries and Aron J. Murphy

The aim of this study was to investigate the kinematics, kinetics, and neural activation of the traditional bench press movement performed explosively and the explosive bench throw in which the barbell was projected from the hands. Seventeen male subjects completed three trials with a bar weight of 45% of the subject's previously determined 1RM. Performance was significantly higher during the throw movement compared to the press for average velocity, peak velocity, average force, average power, and peak power. Average muscle activity during the concentric phase for pectoralis major, anterior deltoid, triceps brachii, and biceps brachii was higher for the throw condition. It was concluded that performing traditional press movements rapidly with light loads does not create ideal loading conditions for the neuromuscular system with regard to explosive strength production, especially in the final stages of the movement, because ballistic weight loading conditions where the resistance was accelerated throughout the movement resulted in a greater velocity of movement, force output, and EMG activity.