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Many prominent intelligence tests (e.g., Wechsler Intelligence Scale for Children, Fifth Edition [WISC-V] and Reynolds Intellectual Abilities Scale, Second Edition [RIAS-2]) offer methods for computing subtest- and composite-level difference scores. This study uses data provided in the technical manual of the WISC-V and RIAS-2 to calculate reliability coefficients for difference scores. Subtest-level difference score reliabilities range from 0.59 to 0.99 for the RIAS-2 and from 0.53 to 0.87 for the WISC-V. Composite-level difference score reliabilities generally range from 0.23 to 0.95 for the RIAS-2 and from 0.36 to 0.87 for the WISC-V. Emphasis is placed on comparisons recommended by test publishers and a discussion of minimum requirements for interpretation of differences scores is provided. 相似文献
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Knechtle B Knechtle P Rosemann T Oliver S 《Research quarterly for exercise and sport》2010,81(3):319-327
A loss in total body mass during an ultraendurance performance is usually attributed to dehydration. We identified the changes in total body mass, fat mass, skeletal muscle mass, and selected markers of hydration status in 31 male nonprofessional ultratriathletes participating in a Triple Iron triathlon involving 11.4 km swimming, 540 km cycling and 126.6 km running. Measurements were taken prior to starting the race and after arrival at the finish line. Total body mass decreased by 1.66 kg (SD = 1.92; -5.3 kg to +1.2 kg; p < .001), skeletal muscle mass by 1.00 kg (SD = 0.90; -2.54 kg to +2.07 kg; p < .001), and fat mass by 0.58 kg (SD = 0.78; -1.74 kg to +0.87 kg; p < .001). The decrease in total body mass was associated with the decrease in skeletal muscle mass (r = .44; p < .05) and fat mass (r = .51; p < .05). Total body water and urinary specific gravity did not significantly change. Plasma urea increased significantly (p < .001); the decrease in skeletal muscle mass and the increase in plasma urea were associated (r = .39; p < .05). We conclude that completing a Triple Iron triathlon leads to decreased total body mass due to reduced fat mass and skeletal muscle mass but not to dehydration. The association of decrease in skeletal muscle mass and increased plasma urea suggests a loss in skeletal muscle mass. 相似文献
96.
James C. Hannon Thomas Ratliffe Daniel P. Williams 《Research quarterly for exercise and sport》2013,84(4):519-526
Purpose: The aim of this study was to examine the effect of active versus passive recovery on 6 repeated Wingate tests (30-s all-out cycling sprints on a Velotron ergometer). Method: Fifteen healthy participants aged 29 (SD = 8) years old (body mass index = 23 [3] kg/m2) participated in 3 sprint interval training sessions separated by 3 to 7 days between each session during a period of 1 month. The 1st visit was familiarization to 6 cycling sprints; the 2nd and 3rd visits involved a warm-up followed by 6 30-s cycling sprints. Each sprint was followed by 4 min of passive (resting still on the ergometer) or active recovery (pedaling at 1.1 W/kg). The same recovery was used within each visit, and recovery type was randomized between visits. Results: Active recovery resulted in a 0.6 W/kg lower peak power output in the second sprint (95% confidence interval [CI] [ ? 0.2, ? 0.8 W/kg], effect size = 0.50, p < .01) and a 0.4 W/kg greater average power output in the 5th and 6th sprints (95% CI [+0.2,+0.6 W/kg], effect size = 0.50, p < .01) compared with passive recovery. There was little difference between fatigue index, total work, or accumulated work between the 2 recovery conditions. Conclusions: Passive recovery is beneficial when only 2 sprints are completed, whereas active recovery better maintains average power output compared with passive recovery when several sprints are performed sequentially (partial eta squared between conditions for multiple sprints = .38). 相似文献
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Jerry R. Thomas Caryl Pierce Susan Ridsdale 《Research quarterly for exercise and sport》2013,84(3):592-597
Abstract In order to investigate the effects of modeling behavior for seven- and nine-year-old children, 30 seven-year-old and 30 nine-year-old females were randomly assigned within age level to three groups. These groups differed according to whether a model was presented at the beginning, midway, or not at all during 12 trials on the stabilometer. Both age groups were found to be similar in performance in the no model condition and, for both age groups, the beginning model condition was found to facilitate performance. However, the introduction of the model after six trials had a detrimental effect on the performance of younger children but facilitated older children's performance. These findings were interpreted in light of a likely increase in the processing capacity of nine year olds as well as an increase in the number of movement schemes that were previously stored in the older girls. 相似文献
99.
Keith?KoenigEmail author Nan?Davis?Mitchell Thomas?E.?Hannigan J.?Keith?Clutter 《Sports Engineering》2004,7(2):105-117
The speed at which a player can swing a bat is central to the games of baseball and softball, determining, to a large extent,
the hit speed of the ball. Experimental and analytical studies of bat swing speed were conducted with particular emphasis
on the influence of bat moment of inertia on swing speed. Two distinct sets of experiments measured the swing speed of colege
baseball and fast-pitch softball players using weighted rods and modified bats. The swing targets included flexible targets,
balls on a tee and machine pitched balls. Internal mass alterations provided a range of inertial properties. The average measured
speeds, from 22 to 31 m s−1, are consistent with previous studies. Bat speed approximately correlates with the moment of inertia of the bat about a vertical
axis of rotation through the batter's body, the speed generally decreasing as this moment of inertia increases. The analytical
model assumes pure rotation of the batter/bat system about a vertical axis through the batter's body. Aerodynamic drag of
the batter's arms and the bat is included in the model. The independent variable is bat moment of inertia about the rotation
axis. There is reasonable agreement between the model and the measured speeds. Detailed differences between the two suggest
the importance of additional degrees of freedom in determining swing speed. 相似文献
100.
Rowe DA McDonald SM Mahar MT Raedeke TD 《Research quarterly for exercise and sport》2005,76(4):407-415
A multitrait-multimethod (MTMM) matrix was used to evaluate validity evidence for a digital image manipulation (DIM) body image measurement technique in young women. One hundred one young women completed the DIM procedure and the Thompson and Gray (1995) Contour Drawing Rating Scale to measure self-ideal discrepancy and size perception accuracy components of body image. Seven-day test-retest reliability was acceptable (R = .81-.95). Convergent validity for self-ideal discrepancy was higher (r = .74) than the corresponding heterotrait, monomethod coefficients (r = .46, r = .23) and heterotrait-heteromethod coefficients (r = .18, r = .12). However, the convergent validity coefficient for size perception accuracy was r = .12. The pattern of correlations in the MTMM matrix met the criteria of Campbell and Fiske (1959) for validity of these procedures to measure self-ideal discrepancy but not size perception accuracy. The DIM procedure addresses some of the criticisms associated with figure-rating scales, such as unrepresentativeness of the figures, scale coarseness, and restriction of range in responses. DIM, therefore, represents a realistic, valid alternative to figure-rating scales for measuring self-ideal discrepancy. 相似文献