학술논문

Reliability and Magnitude of Countermovement Jump Performance Variables: Influence of the Take-off Threshold.
Document Type
Article
Source
Measurement in Physical Education & Exercise Science. Jul-Sep2021, Vol. 25 Issue 3, p227-235. 9p. 2 Charts, 2 Graphs.
Subject
*EXERCISE tests
*CONFIDENCE intervals
*LIFTING & carrying (Human mechanics)
*DESCRIPTIVE statistics
*JUMPING
*ATHLETIC ability
*BIOMECHANICS
Language
ISSN
1091-367X
Abstract
This study explored the influence of different take-off thresholds on the reliability and magnitude of countermovement jump (CMJ) performance variables. Twenty-three men were tested on two separate sessions. CMJ performance variables were obtained against three external loads (0.5–30-60 kg) using three take-off thresholds: 10 N (arbitrary value of 10 N), 5SD (mean value plus 5 standard deviations of the vertical force recorded during the flight phase), and PRF (peak difference between the vertical force trace and 0 N during the flight phase). No significant differences in reliability were observed between the three thresholds (CV and ICC values of one threshold were within 95% CI of the other thresholds). The magnitude of the variables generally differed between the 10 N threshold and the 5SD and PRF thresholds (P <.05), but not between the 5SD and PRF thresholds (P >.05). These results demonstrate that the take-off threshold influences the magnitude of CMJ performance variables but not their reliability. [ABSTRACT FROM AUTHOR]