Reliability of the squat jump force-velocity and load-velocity profiles
Document Type
Journal Article
Publication Title
Journal of Strength and Conditioning Research
PubMed ID
33966009
Publisher
National Strength and Conditioning Association
School
School of Medical and Health Sciences
RAS ID
36601
Abstract
The reliability of the squat jump force-velocity and load-velocity profiles. J Strength Cond Res XX(X): 000-000, 2021-The purpose of this study was to investigate the between-session reliability of the squat jump force-velocity (FV) and load-velocity (LV) profiles. Eighteen subjects (age = 28.1 ± 4.8 years; height = 1.7 ± 9.7; body mass = 74.7 ± 12.8) who could back squat >1.5 times body mass participated in this study. Each subject completed a familiarization session, followed by 2 experimental sessions each separated by 72 hours. Subjects performed a series of squat jumps on a force plate against external loads between 0 and 100% of their body mass in a quasi-randomized block order. Intraclass correlation coefficient (ICC) and coefficient of variation (CV) were used to examine the between-session reliability. Peak velocity (PV) and mean velocity (MV) at each load were highly reliable (ICC >0.80, CV% <7.41, SEM <0.13 m·s-1, smallest detectable difference [SDD] <0.31 m·s-1, ES <0.21). Force-velocity profiles created with peak force and relative peak force resulted in poor to excellent reliability (ICC = 0.34-0.92, CV% = 11.9-26.3). When mean and relative mean forces were used to create FV profiles, there was poor to good reliability (ICC = 0.03-0.85, CV% = 18.1-39.4). When the LV profile was calculated with PV (ICC = 0.60-0.90, CV% = 7.9-16.9) or MV (ICC = 0.49-0.91, CV% = 11.1-23.4), there was poor to excellent reliability. There was no time effect found between sessions for both FV and LV profiles. The squat jump FV and LV profiles established with a force plate are not reliable. Therefore, these profiles are not recommended to be used to inform programming decisions.
DOI
10.1519/JSC.0000000000004057
Access Rights
subscription content
Comments
Kotani, Y., Lake, J., Guppy, S. N., Poon, W., Nosaka, K., Hori, N., & Haff, G. G. (2022). Reliability of the squat jump force-velocity and load-velocity profiles. The Journal of Strength and Conditioning Research, 36(11), 3000-3007.
https://doi.org/10.1519/JSC.0000000000004057