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Thomas Dos’Santos, Paul A. Jones, Jonathan Kelly, John J. McMahon, Paul Comfort and Christopher Thomas

athletes. 19 Variations in IMTP kinetics reported across the literature may be partially explained by methodological differences. 2 , 8 , 13 , 16 , 18 Early research used a sampling frequency of 500 Hz and 600 Hz, 8 , 13 whereas more recent investigations have implemented a sampling frequency of 1000 Hz

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Yani L. Dickens, Judy Van Raalte and Russell T. Hurlburt

-aloud methods presume that thinking translates easily and contemporaneously into words, typically focus on thoughts at the expense of other inner experiences such as emotions or sensations, lack random and representative sampling in favor of ongoing, continuous real-time reporting ( Hurlburt, 2011 ), and may be

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Senia Smoot Reinert, Allison L. Kinney, Kurt Jackson, Wiebke Diestelkamp and Kimberly Bigelow

movement quality because they only give the maximum displacement of COP. However, newer nonlinear analysis methods, such as sample entropy, allow us to describe movement quality. Sample entropy quantifies the underlying regularity of human movements and has been used to study phenomena such as the effect

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Megan S. Patterson and Patricia Goodson

compulsive exercise scores? Based on the tripartite model and previous literature, the investigators expect relationships with peers and family members to significantly impact compulsive exercise scores in the sample. They also hypothesize that having greater body dissatisfaction and exercising more

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Daniel J. Madigan, Thomas Curran, Joachim Stoeber, Andrew P. Hill, Martin M. Smith and Louis Passfield

 al., 2011 ). Notably, Gotwals et al. ( 2010 ) also found coach pressure to predict perfectionistic strivings and perfectionistic concerns in a sample of late-adolescent athletes. Although current findings are suggestive of a link between coach pressure and athlete perfectionism, several issues remain

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Joseph Hamill, Graham E. Caldwell and Timothy R. Derrick

Researchers must be cognizant of the frequency content of analog signals that they are collecting. Knowing the frequency content allows the researcher to determine the minimum sampling frequency of the data (Nyquist critical frequency), ensuring that the digital data will have all of the frequency characteristics of the original signal. The Nyquist critical frequency is 2 times greater than the highest frequency in the signal. When sampled at a rate above the Nyquist, the digital data will contain all of the frequency characteristics of the original signal but may not present a correct time-series representation of the signal. In this paper, an algorithm known as Shannon's Sampling Theorem is presented that correctly reconstructs the time-series profile of any signal sampled above the Nyquist critical frequency. This method is superior to polynomial or spline interpolation techniques in that it can reconstruct peak values found in the original signal but missing from the sampled data time-series.

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Jérôme Vaulerin, Frédéric Chorin, Mélanie Emile, Fabienne d’Arripe-Longueville and Serge S. Colson

the absolute difference between both limbs, in centimeters. The same investigator collected WBLT measures for all participants. Postural Stability The SATEL (SATEL, Blagnac, France) platform was used to assess the displacement of the participants’ center of pressure (COP). The COP data were sampled

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Ryan Morrison, Kyle M. Petit, Chris Kuenze, Ryan N. Moran and Tracey Covassin

. Future research should aim to include equal male and female student-athletes, with a larger sample over a longer period. Observing baseline changes over a college career would give clinicians a better understanding of how often to collect baseline data, as there are no consistent recommendations

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Rand Wilcox, Travis J. Peterson and Jill L. McNitt-Gray

, meaning the probability of detecting a true difference. A positive feature of standard methods for comparing means is that they control the type I error probability reasonably well when observations are sampled from populations of individuals that have identical means, variances, skewness, and so forth

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Thomas Dos’Santos, Paul A. Jones, Jonathan Kelly, John J. McMahon, Paul Comfort and Christopher Thomas

Purpose:

Skeletal-muscle function can be evaluated using force–times curves generated via the isometric midthigh pull (IMTP). Various sampling frequencies (500–1000 Hz) have been used for IMTP assessments; however, no research has investigated the influence of sampling frequency on IMTP kinetics. Therefore, the purpose of this study was to investigate the influence of sampling frequency on kinetic variables during the IMTP, including peak force, time-specific force values (100, 150, and 200 ms), and rate of force development (RFD) at 3 time bands (0–100, 0–150, 0–200 ms).

Methods:

Academy rugby league players (n = 30, age 17.5 ± 1.1 y, height 1.80 ± 0.06 m, mass 85.4 ± 10.3 kg) performed 3 IMTP trials on a force platform sampling at 2000 Hz, which was subsequently down-sampled to 1500, 1000, and 500 Hz for analysis.

Results:

Intraclass correlation coefficients (ICC) and coefficients of variation (CV) demonstrated high within-session reliability for all force and RFD variables across all sampling frequencies (ICC ≥ .80, CV ≤ 10.1%). Repeated-measures analysis of variance revealed no significant differences (P > .05, Cohen d ≤ 0.009) in kinetic variables between sampling frequencies. Overall, high reliability was observed across all sampling frequencies for all kinetic variables, with no significant differences (P > .05) for each kinetic variable across sampling frequencies.

Conclusions:

Practitioners and scientists may consider sampling as low as 500 Hz when measuring peak force, time-specific force values, and RFD at predetermined time bands during the IMTP for accurate and reliable data.