| Title: | Association of sedentary and physical activity behaviours with body composition: a genome-wide association and Mendelian randomisation study |
| Journal: | BMJ Open Sport & Exercise Medicine |
| Published: | 2 Aug 2022 |
| Pubmed: | https://pubmed.ncbi.nlm.nih.gov/35990758/ |
| DOI: | https://doi.org/10.1136/bmjsem-2021-001291 |
| URL: | https://bmjopensem.bmj.com/content/bmjosem/8/3/e001291.full.pdf |
Publication 14122
WARNING: the interactive features of this website use CSS3, which your browser does not support. To use the full features of this website, please update your browser.
Abstract
Objectives: Studies suggest that body composition can be independently improved through physical activity (PA). We performed a Mendelian randomisation (MR) study to test the incremental benefits of sedentary behaviour and various PA exposures on body composition outcomes as assessed by anthropometric indices, lean body mass (kg), body fat (%) and visceral adipose tissue (VAT) (kg).</p>
Methods: Genetic instruments were identified for both self-reported and accelerometer-measured sedentary behaviour and PA. Outcomes included anthropometric and dual-energy X-ray absorptiometry measures of adiposity, extracted from the UK Biobank and the largest available consortia. Multivariable MR (MVMR) included educational attainment as a covariate to address potential confounding. Sensitivity analyses were evaluated for weak instrument bias and pleiotropic effects.</p>
Results: We did not identify consistent associations between genetically predicted self-reported and accelerometer-measured sedentary behaviour and body composition outcomes. All analyses for self-reported moderate PA were null for body composition outcomes. Genetically predicted PA at higher intensities was protective against VAT in MR and MVMR analyses of both accelerometer-measured vigorous PA (MVMR β=-0.15, 95% CI: -0.24 to -0.07, p<0.001) and self-reported participation in strenuous sports or other exercises (MVMR β=-0.27, 95% CI: -0.52 to -0.01, p=0.034) was robust across several sensitivity analyses.</p>
Conclusions: We did not identify evidence of a causal relationship between genetically predicted PA and body composition, with the exception of a putatively protective effect of higher-intensity PA on VAT. Protective effects of PA against VAT may support prior evidence of biological pathways through which PA decreases risk of downstream cardiometabolic diseases.</p>
7 Authors
- Ferris A Ramadan
- Jennifer W Bea
- David O Garcia
- Katherine D Ellingson
- Robert A Canales
- David A Raichlen
- Yann C Klimentidis
Enabling scientific discoveries that improve human health