Knee extensor strength differences in obese and healthy-weight 10-13 year olds

Tsiros, Margarita, Coates , Alison, Howe, Peter, Grimshaw, Paul, Walkley, Jeff, Shield, Anthony, Mallows, Richard, Hills, Andrew P., Kagawa, Masaharu , Shultz, Sarah, & Buckley, Jonathan (2013) Knee extensor strength differences in obese and healthy-weight 10-13 year olds. European Journal of Applied Physiology, 113(6), pp. 1415-1422.

View at publisher


The purpose of this study was to investigate if obese children have reduced knee extensor (KE) strength and to explore the relationship between adiposity and KE strength. An observational case-control study was conducted in three Australian states, recruiting obese [n=107 (51 female, 56 male)] and healthy-weight [n=132 (56 female, 76 male)] 10–13 year old children. Body mass index, body composition (dual energy X-ray absorptiometry), isokinetic/isometric peak KE torques (dynamometry) and physical activity (accelerometry) were assessed. Results revealed that compared with their healthy-weight peers, obese children had higher absolute KE torques (P≤0.005), equivocal KE torques when allometrically normalized for fat-free mass (FFM) (P≥0.448) but lower relative KE torques when allometrically normalized for body mass (P≤0.008). Adjustments for maternal education, income and accelerometry had little impact on group differences, except for isometric KE torques relative to body mass which were no longer significantly lower in obese children (P≥0.013, not significant after controlling for multiple comparisons). Percent body fat was inversely related to KE torques relative to body mass (r= -0.22 to -0.35, P≤0.002), irrespective of maternal education, income or accelerometry. In conclusion, while obese children have higher absolute KE strength and FFM, they have less functional KE strength (relative to mass) available for weight-bearing activities than healthy-weight children. The finding that FFM-normalized KE torques did not differ suggests that the intrinsic contractile properties of the KE muscles are unaffected by obesity. Future research is needed to see if deficits in KE strength relative to mass translate into functional limitations in weight-bearing activities.

Impact and interest:

11 citations in Scopus
Search Google Scholar™
8 citations in Web of Science®

Citation counts are sourced monthly from Scopus and Web of Science® citation databases.

These databases contain citations from different subsets of available publications and different time periods and thus the citation count from each is usually different. Some works are not in either database and no count is displayed. Scopus includes citations from articles published in 1996 onwards, and Web of Science® generally from 1980 onwards.

Citations counts from the Google Scholar™ indexing service can be viewed at the linked Google Scholar™ search.

Full-text downloads:

227 since deposited on 19 Nov 2012
27 in the past twelve months

Full-text downloads displays the total number of times this work’s files (e.g., a PDF) have been downloaded from QUT ePrints as well as the number of downloads in the previous 365 days. The count includes downloads for all files if a work has more than one.

ID Code: 54841
Item Type: Journal Article
Refereed: Yes
Keywords: obese children , knee extensor , adiposity
DOI: 10.1007/s00421-012-2561-z
ISSN: 1439-6319
Subjects: Australian and New Zealand Standard Research Classification > MEDICAL AND HEALTH SCIENCES (110000) > HUMAN MOVEMENT AND SPORTS SCIENCE (110600) > Human Movement and Sports Science not elsewhere classified (110699)
Divisions: Current > QUT Faculties and Divisions > Faculty of Health
Current > Institutes > Institute of Health and Biomedical Innovation
Current > Schools > School of Exercise & Nutrition Sciences
Copyright Owner: Copyright 2012 Springer-Verlag
Copyright Statement: The original publication is available at SpringerLink
Deposited On: 19 Nov 2012 22:58
Last Modified: 05 Sep 2013 10:15

Export: EndNote | Dublin Core | BibTeX

Repository Staff Only: item control page