Yoga in women with abdominal obesity - Do lifestyle factors mediate the effect? Secondary analysis of a RCT.

INTRODUCTION

The reduction of obesity is an important challenge for health policy. Although dietary interventions are widely available, patient adherence is usually low. A promising alternative is yoga. We hypothesized that weight reduction through yoga is mediated by aspects related to eating habits as well as physical aspects.

METHODS

This is an exploratory secondary analysis of a randomized controlled trial comparing the effects of yoga to waiting list in women with abdominal obesity. Body mass index (BMI) and waist circumference were assessed as outcomes; physical exercise habits, physical activity habits at leisure time, physical activity habits at work time, daily fruit and vegetable intake, nutrition self-efficacy, and physical self-efficacy were captured as mediators. Measures were assessed at weeks 0 and 12. The original trial was conducted between April and August 2015. The secondary analysis was performed December 2019.

RESULTS

Forty patients were randomized to the 12 weekly yoga sessions (48.5 ± 7.9 years) and 20 patients to the waitlist group (46.4 ± 8.9 years). Physical exercise habits fully mediated the effect of yoga on BMI (B=-0.26;CI[-.56;-.07]). Daily fruit and vegetable intake partially mediated the effect of yoga on BMI (B=-0.13;CI[-.38;-.01]). No further mediation effects were found.

CONCLUSIONS

Yoga supports people with overweight in eating healthier and increasing their physical activity which in turn leads to a reduced BMI. Yoga's effects on waist circumference seem to be due to other mechanisms.