Important components of yoga practice for mediating the stress response

Abstract

Multimodal yoga practice has become a popular adjuvant treatment for lifestyle diseases. This thesis aimed to understand the typical composition of yoga classes of different styles, evaluated the evidence of the effects of the class components on stress reactivity and compared the effects of traditional yoga (including pranayama, meditation, chanting, relaxation) with exercise-based yoga (including only postures) on stress reactivity. In an online survey of yoga teachers (n=968), the reported styles were categorized into three styles: ‘traditional yoga’, ‘exercise-based yoga’, ‘therapy yoga’. A greater proportion of traditional teachers included pranayama, chanting, and cleansing in classes compared to exercise-based and therapy teachers. The duration of non-physical components (breathing, meditation, relaxation and chanting) was greater in the traditional and therapy compared to exercise-based classes. In a systematic review, 21 out of 28 studies (n=2574) including 31 interventions of meditation (n=22), breathing (n=4) and yoga (n=5) found beneficial effects of all types of intervention on stress reactivity. The final RCT study (n=68), found that traditional yoga lowered anxiety and negative affect, and increased positive affect. Traditional yoga led to reduced sympathetic activation and increased parasympathetic activation in response to stress compared to exercise-based yoga. This thesis found that most yoga styles practiced around the world, include diverse yoga components, but that inclusion and duration of non-physical components was typically greater in traditional styles. This thesis found that traditional yoga practice incorporating greater duration of non-physical components is superior to moderate intensity exercise-based yoga and light intensity exercise in mitigating acute stress responses, proposed to be due to the additive effects of components which were shown to have separate stress-attenuating effects.