Muscle activation patterns in the Nordic hamstring exercise: Impact of prior strain injury
File version
Accepted Manuscript (AM)
Author(s)
Opar, DA
Williams, MD
Al Najjar, A
Shield, AJ
Griffith University Author(s)
Primary Supervisor
Other Supervisors
Editor(s)
Date
Size
File type(s)
Location
License
Abstract
This study aimed to determine: (a) the spatial patterns of hamstring activation during the Nordic hamstring exercise (NHE); (b) whether previously injured hamstrings display activation deficits during the NHE; and (c) whether previously injured hamstrings exhibit altered cross‐sectional area (CSA). Ten healthy, recreationally active men with a history of unilateral hamstring strain injury underwent functional magnetic resonance imaging of their thighs before and after six sets of 10 repetitions of the NHE. Transverse (T2) relaxation times of all hamstring muscles [biceps femoris long head (BFlh); biceps femoris short head (BFsh); semitendinosus (ST); semimembranosus (SM)] were measured at rest and immediately after the NHE and CSA was measured at rest. For the uninjured limb, the ST's percentage increase in T2 with exercise was 16.8%, 15.8%, and 20.2% greater than the increases exhibited by the BFlh, BFsh, and SM, respectively (P < 0.002 for all). Previously injured hamstring muscles (n = 10) displayed significantly smaller increases in T2 post‐exercise than the homonymous muscles in the uninjured contralateral limb (mean difference −7.2%, P = 0.001). No muscles displayed significant between‐limb differences in CSA. During the NHE, the ST is preferentially activated and previously injured hamstring muscles display chronic activation deficits compared with uninjured contralateral muscles.
Journal Title
Scandinavian Journal of Medicine & Science in Sports
Conference Title
Book Title
Edition
Volume
26
Issue
6
Thesis Type
Degree Program
School
Publisher link
Patent number
Funder(s)
Grant identifier(s)
Rights Statement
Rights Statement
© 2016 Blackwell Verlag GmbH. This is the peer reviewed version of the following article: Muscle activation patterns in the Nordic hamstring exercise: Impact of prior strain injury, Scandinavian Journal of Medicine & Science in Sports, Volume26, Issue6, Pages 666-674, which has been published in final form at 10.1111/sms.12494. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving (http://olabout.wiley.com/WileyCDA/Section/id-828039.html)
Item Access Status
Note
Access the data
Related item(s)
Subject
Sports science and exercise
Sports science and exercise not elsewhere classified
Medical physiology