Objectives: Yoga is a popular form of exercise in the Western world, and yoga's effects on pulmonary function have been investigated previously. The purpose of this article is to review this research systematically and determine if regular yoga training improves pulmonary function in apparently healthy individuals.
Methods: Using the Alternative Health Watch, the Physical Education Index, Medline,(®) and the SPORTdiscus databases; and the keywords yoga, respiration, and pulmonary function, a comprehensive search was conducted that yielded 57 studies. Of these studies selections were made to include only experimental studies written in English, published in peer-reviewed journals after 1980, and investigating the effects of regular yoga practice on pulmonary function in healthy individuals participating in the studies.
Results: Yoga improved pulmonary function, as measured by maximum inspiratory pressure, maximum expiratory pressure, maximum voluntary ventilation, forced vital capacity, forced expiratory volume in 1 second, and peak expiratory flow rate, in all (N=9), but 1, study.
Conclusions: Overall, pulmonary function appears to improve with a minimum of 10 weeks of regular yoga practice, and the magnitude of this improvement is related to fitness level and/or the length of time the subjects spend practicing pranayama (i.e., breathing exercises). In other words, greater improvements in pulmonary function are more likely to be seen in less-fit individuals and/or those that engage in longer periods of pranayama. Additional studies examining various yoga practices are warranted to gain a more comprehensive understanding of the effects of yoga techniques on pulmonary functions.