OBJECTIVE To evaluate the effect of yoga on forced vital capacity (FVC), forced expiratory volume in I(st) second (FEV1), peak expiratory flow rate (PEFR), FEVI/FVC ratio, and pulmonary pressures [maximum inspiratory pressure (MIP), maximum expiratory pressure (MEP) at the end of 3 months yoga training and the detraining effect on the above parameters in 7-9-years-old school going children. METHODS A total of 100 participants were recruited from a school in Bangalore. After baseline assessments, the participants were randomly allocated to either yoga or physical activity group. Intervention was given for 3 months, and measures of pulmonary function and pulmonary pressures were determined immediately post-intervention and at 3-months follow-up. RESULTS Although significant increase was observed in FVC, FEV1, PEFR, FEV1/FVC, MIP, and MEP at post-intervention, there were no significant differences between the two study groups after adjusting for height and age post training . However, MIP increased significantly in both the groups post-intervention, but the yoga group performed significantly higher than the PE group. The effects of training did not fade off even after 3 months of detraining. In fact, the FVC and FEV1 continued to increase significantly. A trend of decrease was observed in PEFR, MIP, and MEP. However, the values did not regress to the baseline value. CONCLUSIONS This study suggests that practice of yoga for a short duration (3 months) of time can significantly improve respiratory muscle strength in pediatric population.