As this study points out yoga practiced over varying durations has been shown to reduce anxiety. The investigation "involved 300 naive-to-yoga persons of both sexes who were attending a yoga therapy center in north India for stress relief as day visitors. . . . They were divided into two groups, yoga practice and yoga theory, and their state anxiety was assessed before and after a 2-hr. yoga session."
"A significant reduction in scores on state anxiety was found in the yoga practice group (14.7% decrease), as well as in the yoga theory group (3.4% decrease). The difference in scores following the sessions was statistically significant. Hence, yoga practice as well as learning about theoretical aspects of yoga appear to reduce state anxiety, with a greater reduction following yoga practice." Abstract: PubMed. Article by S. Telles, V. Gaur, and A. Balkrishna, "Effect of a yoga practice session and a yoga theory session on state anxiety," Perceptual and Motor Skills [2009 Dec;109(3):924-30]
