hh.sePublications
Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Electromyography Muscle Activity in Unilateral and Bilateral Squats with Relative Loads
Halmstad University, School of Business, Engineering and Science, Biological and Environmental Systems (BLESS), Biomechanics and Biomedicine.ORCID iD: 0000-0002-9337-5113
Halmstad University, School of Business, Engineering and Science, Biological and Environmental Systems (BLESS).
2015 (English)Conference paper, Poster (with or without abstract) (Other academic)
Abstract [en]

Introduction

Unilateral strength training is becoming popular as a complement to bilateral training particularly in athletes active in sports performed primarily on one leg. Some studies have shown improved performance after unilateral compared to bilateral strength training, however the underlying cause for this improvement is unclear. The aim of this study was to compare electromyography (EMG) muscle activity in unilateral and bilateral squats performed with 80% of 1repetition maximum (RM) performed in a smith machine.

Methods

Participants in the study were 12 healthy women and men (mean age 25±2 years) with previous weight-lifting experience. EMG activity was measured during the concentric phase in the muscles vastus lateralis, biceps femoris, gluteus medius and erector spinae during A) a maximal voluntary isometric contraction (MVIC), B) 1RM squat (90 degree knee flexion) bilaterally and unilaterally, and C) 3 repetitions 80% of 1RM for both the unilateral and bilateral stance, where each squat was performed at a set speed with the aid of a metronome.

Results

EMG activities, calculated as percent of MVIC, in thigh and hip muscles (vastus lateralis, biceps femoris, gluteus medius) were significantly higher (p<0.01 for all) in the unilateral compared to the bilateral stance. The highest increase in EMG activity was in the gluteus medius where the unilateral squat elicited a 2.9 increase compared to bilateral stance. Unilateral stance muscle activation was in vastus lateralis 1.2 times higher and in biceps femoris 1.5 times higher compared to the bilateral stance. For the trunk muscle erector spinae, the opposite was apparent. EMG activity was 0.6 times lower (p<0.01) when the squat was performed unilaterally compared to bilaterally.

Discussion

Even when the load is made relative to the 1RM for each stance the muscles in especially the gluteus medius but also vastus lateralis and biceps femoris is activated to a higher degree when performed unilaterally which could be a partial explanation as to why the unilateral stance can be beneficial to include in a strength training regime despite the absolute load being lower.

Place, publisher, year, edition, pages
2015.
National Category
Natural Sciences
Identifiers
URN: urn:nbn:se:hh:diva-30088OAI: oai:DiVA.org:hh-30088DiVA: diva2:888147
Conference
20th annual ECSS Congress, Malmö, Sweden, June 24-27, 2015
Funder
Knowledge Foundation
Available from: 2015-12-22 Created: 2015-12-22 Last updated: 2017-08-18Bibliographically approved

Open Access in DiVA

No full text

Search in DiVA

By author/editor
Olsson, M CharlotteFrandsen, Björn
By organisation
Biomechanics and BiomedicineBiological and Environmental Systems (BLESS)
Natural Sciences

Search outside of DiVA

GoogleGoogle Scholar

Total: 370 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf