Document Type

Peer-Reviewed Article

Publication Date

2018

Abstract

The purpose of this study was to examine the force-time differences between concentric-only half-squats (COHS) performed with ballistic (BAL) or non-ballistic (NBAL) intent across a range of loads. Eighteen resistance-trained men performed either BAL or NBAL COHS at 30%, 50%, 70%, and 90% of their one repetition maximum (1RM) COHS. Relative peak force (PF) and relative impulse from 0⁻50 ms (Imp50), 0⁻90 ms (Imp90), 0⁻200 ms (Imp200), and 0⁻250 ms (Imp250) were compared using a series of 2 × 4 (intent × load) repeated measures ANOVAs with Bonferroni post hoc tests. Cohen's d effect sizes were calculated to provide measures of practical significance between the BAL and NBAL COHS and each load. BAL COHS produced statistically greater PF than NBAL COHS at 30% (d = 3.37), 50% (d = 2.88), 70% (d = 2.29), and 90% 1RM (d = 1.19) (all p < 0.001). Statistically significant main effect differences were found between load-averaged BAL and NBAL COHS for Imp90 (p = 0.006, d = 0.25), Imp200 (p = 0.001, d = 0.36), and Imp250 (p < 0.001, d = 0.41), but not for Imp50 (p = 0.018, d = 0.21). Considering the greater PF and impulse observed during the BAL condition, performing COHS with BAL intent may provide a favorable training stimulus compared to COHS performed with NBAL intent.

Comments

This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/).

DOI

10.3390/sports6030079.

PMID

30103536

Publication

Sports

Volume

6

Issue

3

Publisher

MDPI

Creative Commons License

Creative Commons Attribution 4.0 International License
This work is licensed under a Creative Commons Attribution 4.0 International License.

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