Muscle strength and body composition in obese adults following nine months of yoga or nutrition advice: A comparative controlled trial

Introduction: Muscle strength is impaired in obese persons due to low physical activity, obesity-related modifications in muscle morphology and as a consequence of calorie regulation (where applicable). Previously decreased BMI and increased hand grip strength was reported following a short duration yoga intervention in obese adults. Methods: The present comparative controlled study was conducted on two hundred and ninety seven obese adults (BMI >= 25 Kg/M-2) aged between 20 and 59 years, to determine the effects of nine months of yoga or nutrition advice on muscle strength and body composition. Participants were assessed for bilateral hand grip strength, leg and back strength, and body composition at baseline, after 3 months, 6 months and 9 months of yoga or nutrition advice. BMI-adjusted bilateral hand grip strength and leg and back strength were calculated. Results: In the linear mixed model analyses, there was a significant interaction effect of Time X Groups for (i) right hand grip strength (F-3,F-668.465 = 9.297, p < 0.001), (ii) left hand grip strength (F-3,F-673.408 = 14.469, p < 0.001), (iii) BMI-adjusted right hand grip strength (F-3,F-650.542 = 9.954, p < 0.001) and (iv) BMI-adjusted left hand grip strength (F-3,F-655.518 = 13.853, p < 0.001). Bonferroni corrected post-hoc analyses (padj < 0.05; in all cases) showed a significant increase in (i) bilateral hand grip strength and (ii) BMI-adjusted right and left hand grip strength in the yoga group while a decrease in (i) bilateral hand grip strength and (ii) BMI-adjusted right and left hand grip strength in the nutrition advice group. Conclusion: Yoga practice appears to protect and increase upper limb muscle strength in obese adults.