Body Mass Index and Waist–Hip Ratio Responses to 16 Week Yoga in Female College Students

Abstract

Background: Indian women frequently carry excess and abdominal fat, and weight tends to climb during early adulthood. Whether yoga lowers body mass index (BMI) and waist–hip ratio (WHR) in young women is uncertain.
Objective: To test whether 16 weeks of supervised yoga changes BMI and WHR in female college students.
Methods: In this single-blind, two-arm, pragmatic, parallel-group randomized controlled trial (RCT) at two colleges in Telangana, India, 332 of 375 female D.Ed., B.Ed. and undergraduate degree students were randomized to a yoga group (YG; n = 164) or a control group (CG; n = 168). The YG practised loosening exercises, Surya Namaskar, asanas, pranayama, Jalandhara Bandha and relaxation for 60 min/day, 5 days/week; controls kept their usual routine. After 32 dropouts, 150 per group were analysed with paired and independent-samples t tests and analysis of covariance (ANCOVA).
Results: Post-test BMI was 24.24 ± 3.24 kg/m² in the YG versus 29.95 ± 5.22 kg/m² in the CG (mean difference [MD] −5.71 kg/m²; 95% CI −6.70 to −4.73; p < .001). Post-test WHR was 0.755 ± 0.032 versus 0.819 ± 0.048 (MD −0.065; 95% CI −0.074 to −0.055; p < .001). Within the YG, BMI dropped by 4.67 kg/m² and WHR by 0.052; within the CG, both rose slightly. Results held when dropouts were imputed.
Conclusion: Sixteen weeks of supervised yoga was associated with lower BMI and WHR than usual routine. Effects exceeded earlier reports and diet was unrecorded, so replication with dietary assessment, longer follow-up and other populations is needed.