Objectively measured physical activity and fat mass in a large cohort of children

Ness, A.R., Leary, S.D., Mattocks, C., Blair, S.N., Reilly, J.J., Wells, J., Ingle, S., Tilling, K., Davey Smith, G. and Riddoch, C. (2007) Objectively measured physical activity and fat mass in a large cohort of children. PLoS Medicine, 4(3), e97. (doi: 10.1371/journal.pmed.0040097)

Abstract

Background Previous studies have been unable to characterise the association between physical activity and obesity, possibly because most relied on inaccurate measures of physical activity and obesity. Methods and Findings We carried out a cross sectional analysis on 5,500 12-year-old children enrolled in the Avon Longitudinal Study of Parents and Children. Total physical activity and minutes of moderate and vigorous physical activity (MVPA) were measured using the Actigraph accelerometer. Fat mass and obesity (defined as the top decile of fat mass) were measured using the Lunar Prodigy dual x-ray emission absorptiometry scanner. We found strong negative associations between MVPA and fat mass that were unaltered after adjustment for total physical activity. We found a strong negative dose-response association between MVPA and obesity. The odds ratio for obesity in adjusted models between top and the bottom quintiles of minutes of MVPA was 0.03 (95% confidence interval [CI] 0.01-0.13, p-value for trend < 0.0001) in boys and 0.36 (95% CI 0.17-0.74, p-value for trend = 0.006) in girls. Conclusions We demonstrated a strong graded inverse association between physical activity and obesity that was stronger in boys. Our data suggest that higher intensity physical activity may be more important than total activity.

• Item Type: Articles
• Additional Information: This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Davey Smith, Professor George and Reilly, Prof John
• Authors: Ness, A.R., Leary, S.D., Mattocks, C., Blair, S.N., Reilly, J.J., Wells, J., Ingle, S., Tilling, K., Davey Smith, G., and Riddoch, C.
• College/School: College of Medical Veterinary and Life Sciences > School of Medicine, Dentistry & Nursing
• Journal Name: PLoS Medicine
• Publisher: Public Library of Science
• ISSN: 1549-1277
• ISSN (Online): 1549-1676
• Published Online: 01 January 2007
• Copyright Holders: © 2007 Ness et al.
• First Published: First published in PLoS Medicine 2007 4(3): e97
• Publisher Policy: Reproduced in accordance with the copyright policy of the publisher