Influence of different loads on force-time characteristics during back squats

Takafumi Kubo, Kuniaki Hirayama, Nobuhiro Nakamura, Mitsuru Higuchi

Research output: Contribution to journalArticle

Abstract

The deceleration sub-phase during the back squat (BSQ) makes it difficult to stimulate the muscles throughout the full range of motion, and it has only been reported for one load during BSQ. The purpose of this study was to investigate whether a deceleration sub-phase occurs during BSQ with different loads and to assess the influence of load on the deceleration sub-phase duration and negative impulse during the deceleration sub-phase. Sixteen healthy men (mean ± standard deviation: age: 25 ± 3 years; height: 1.73 ± 0.07 m; mass: 83.2 ± 16.1 kg; BSQ one repetition maximum (1RM): 163.8 ± 36.6 kg; BSQ 1RM/body weight: 2.0 ± 0.4) who had performed resistance training for at least 1 year were recruited for this study. The subjects performed parallel BSQ with 0%, 12%, 27%, 42%, 56%, 71%, and 85% of each 1RM on a force plate in a random order. The deceleration sub-phase duration and negative impulse during the deceleration sub-phase were calculated from force-time data. The absolute durations of the deceleration sub-phase were not significantly different according to load except for 27% 1RM and 85% 1RM (p = 0.01). However, as the load increased from 12 to 85% 1RM, the relative duration of the deceleration sub-phase decreased (p < 0.05). The negative impulse during the deceleration sub-phase also increased from 0 to 42% 1RM (p < 0.05). A deceleration sub-phase occurs regardless of the load (0%–85% 1RM), and a large portion of the deceleration sub-phase occupied the concentric phase, with low–moderate loads, and a large amount of negative impulse occurred during the short deceleration sub-phase with a high load.

Original languageEnglish
Pages (from-to)617-622
Number of pages6
JournalJournal of Sports Science and Medicine
Volume17
Issue number4
Publication statusPublished - 2018 Jan 1

Fingerprint

Deceleration
Resistance Training
Articular Range of Motion
Body Weight

Keywords

  • Power
  • Resistance exercise
  • Strength

ASJC Scopus subject areas

  • Orthopedics and Sports Medicine
  • Physical Therapy, Sports Therapy and Rehabilitation

Cite this

Influence of different loads on force-time characteristics during back squats. / Kubo, Takafumi; Hirayama, Kuniaki; Nakamura, Nobuhiro; Higuchi, Mitsuru.

In: Journal of Sports Science and Medicine, Vol. 17, No. 4, 01.01.2018, p. 617-622.

Research output: Contribution to journalArticle

Kubo, Takafumi ; Hirayama, Kuniaki ; Nakamura, Nobuhiro ; Higuchi, Mitsuru. / Influence of different loads on force-time characteristics during back squats. In: Journal of Sports Science and Medicine. 2018 ; Vol. 17, No. 4. pp. 617-622.
@article{f8392e8e70404bca8366bf2fc6d5b474,
title = "Influence of different loads on force-time characteristics during back squats",
abstract = "The deceleration sub-phase during the back squat (BSQ) makes it difficult to stimulate the muscles throughout the full range of motion, and it has only been reported for one load during BSQ. The purpose of this study was to investigate whether a deceleration sub-phase occurs during BSQ with different loads and to assess the influence of load on the deceleration sub-phase duration and negative impulse during the deceleration sub-phase. Sixteen healthy men (mean ± standard deviation: age: 25 ± 3 years; height: 1.73 ± 0.07 m; mass: 83.2 ± 16.1 kg; BSQ one repetition maximum (1RM): 163.8 ± 36.6 kg; BSQ 1RM/body weight: 2.0 ± 0.4) who had performed resistance training for at least 1 year were recruited for this study. The subjects performed parallel BSQ with 0{\%}, 12{\%}, 27{\%}, 42{\%}, 56{\%}, 71{\%}, and 85{\%} of each 1RM on a force plate in a random order. The deceleration sub-phase duration and negative impulse during the deceleration sub-phase were calculated from force-time data. The absolute durations of the deceleration sub-phase were not significantly different according to load except for 27{\%} 1RM and 85{\%} 1RM (p = 0.01). However, as the load increased from 12 to 85{\%} 1RM, the relative duration of the deceleration sub-phase decreased (p < 0.05). The negative impulse during the deceleration sub-phase also increased from 0 to 42{\%} 1RM (p < 0.05). A deceleration sub-phase occurs regardless of the load (0{\%}–85{\%} 1RM), and a large portion of the deceleration sub-phase occupied the concentric phase, with low–moderate loads, and a large amount of negative impulse occurred during the short deceleration sub-phase with a high load.",
keywords = "Power, Resistance exercise, Strength",
author = "Takafumi Kubo and Kuniaki Hirayama and Nobuhiro Nakamura and Mitsuru Higuchi",
year = "2018",
month = "1",
day = "1",
language = "English",
volume = "17",
pages = "617--622",
journal = "Journal of Sports Science and Medicine",
issn = "1303-2968",
publisher = "Department of Sports Medicine, Medical Faculty of Uludag University",
number = "4",

}

TY - JOUR

T1 - Influence of different loads on force-time characteristics during back squats

AU - Kubo, Takafumi

AU - Hirayama, Kuniaki

AU - Nakamura, Nobuhiro

AU - Higuchi, Mitsuru

PY - 2018/1/1

Y1 - 2018/1/1

N2 - The deceleration sub-phase during the back squat (BSQ) makes it difficult to stimulate the muscles throughout the full range of motion, and it has only been reported for one load during BSQ. The purpose of this study was to investigate whether a deceleration sub-phase occurs during BSQ with different loads and to assess the influence of load on the deceleration sub-phase duration and negative impulse during the deceleration sub-phase. Sixteen healthy men (mean ± standard deviation: age: 25 ± 3 years; height: 1.73 ± 0.07 m; mass: 83.2 ± 16.1 kg; BSQ one repetition maximum (1RM): 163.8 ± 36.6 kg; BSQ 1RM/body weight: 2.0 ± 0.4) who had performed resistance training for at least 1 year were recruited for this study. The subjects performed parallel BSQ with 0%, 12%, 27%, 42%, 56%, 71%, and 85% of each 1RM on a force plate in a random order. The deceleration sub-phase duration and negative impulse during the deceleration sub-phase were calculated from force-time data. The absolute durations of the deceleration sub-phase were not significantly different according to load except for 27% 1RM and 85% 1RM (p = 0.01). However, as the load increased from 12 to 85% 1RM, the relative duration of the deceleration sub-phase decreased (p < 0.05). The negative impulse during the deceleration sub-phase also increased from 0 to 42% 1RM (p < 0.05). A deceleration sub-phase occurs regardless of the load (0%–85% 1RM), and a large portion of the deceleration sub-phase occupied the concentric phase, with low–moderate loads, and a large amount of negative impulse occurred during the short deceleration sub-phase with a high load.

AB - The deceleration sub-phase during the back squat (BSQ) makes it difficult to stimulate the muscles throughout the full range of motion, and it has only been reported for one load during BSQ. The purpose of this study was to investigate whether a deceleration sub-phase occurs during BSQ with different loads and to assess the influence of load on the deceleration sub-phase duration and negative impulse during the deceleration sub-phase. Sixteen healthy men (mean ± standard deviation: age: 25 ± 3 years; height: 1.73 ± 0.07 m; mass: 83.2 ± 16.1 kg; BSQ one repetition maximum (1RM): 163.8 ± 36.6 kg; BSQ 1RM/body weight: 2.0 ± 0.4) who had performed resistance training for at least 1 year were recruited for this study. The subjects performed parallel BSQ with 0%, 12%, 27%, 42%, 56%, 71%, and 85% of each 1RM on a force plate in a random order. The deceleration sub-phase duration and negative impulse during the deceleration sub-phase were calculated from force-time data. The absolute durations of the deceleration sub-phase were not significantly different according to load except for 27% 1RM and 85% 1RM (p = 0.01). However, as the load increased from 12 to 85% 1RM, the relative duration of the deceleration sub-phase decreased (p < 0.05). The negative impulse during the deceleration sub-phase also increased from 0 to 42% 1RM (p < 0.05). A deceleration sub-phase occurs regardless of the load (0%–85% 1RM), and a large portion of the deceleration sub-phase occupied the concentric phase, with low–moderate loads, and a large amount of negative impulse occurred during the short deceleration sub-phase with a high load.

KW - Power

KW - Resistance exercise

KW - Strength

UR - http://www.scopus.com/inward/record.url?scp=85057158183&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=85057158183&partnerID=8YFLogxK

M3 - Article

C2 - 30479530

AN - SCOPUS:85057158183

VL - 17

SP - 617

EP - 622

JO - Journal of Sports Science and Medicine

JF - Journal of Sports Science and Medicine

SN - 1303-2968

IS - 4

ER -