Introduction

The Indian Ocean tsunami which occurred in December 2004 affected various parts of South-East Asia including the Andaman Islands. These islands consist of an archipelago in the Bay of Bengal, inhabited by hunter- gatherers who are believed to have originated from the Paleolithic age and Neolithic colonies of South-East Asia (1). The present population includes the endogenous people (EP) as well as settlers from the mainland (ML), i.e. India. A month after the tsunami there was an initiative to introduce stress management techniques for the people who were temporarily relocated in camps in the capital (Port Blair), as their homes were destroyed. At that stage their immediate needs were provided. However, most of them were anxious and distressed, this being related to (i) the possible recurrence of the tsunami especially in the presence of ‘after-shocks’, (ii) being displaced and (iii) reconstructing their lives. Most of them also had to come to terms with losing their relatives, friends and property. As a part of this initiative a survey was conducted on 646 people of whom 328 were endogenous people and 318 were mainland settlers (2). The two populations differed in their: (i) social organization, as the EP group form close communities under a ‘tribal leader’, whereas the ML group has the family as the main unit and (ii) religion, as most of the EP group follow Christianity, whereas most of the ML group are Hindus. The ML group had higher levels for four indicators of distress (i.e. anxiety, fear, sadness and disturbed sleep) which are commonly reported by disaster survivors (3). The groups also differed in their coping strategies with the EP group choosing interpersonal contact while the ML group chose denial strategies especially alcohol. Yoga is an ancient Indian science which includes the practice of loosening exercises ( sithilikarana vyayama), specific postures ( asanas ), cleansing practices (kriyas ), voluntarily regulated breathing (pranayamas ), yoga-based guided relaxation and meditation (dhyana) (4). Yoga training has been reported to decrease heart rate and breath rate, the signs of reduced psycho-physiological arousal in normal volunteers (5). Significant reductions were shown for depression, anger, anxiety, neurotic symptoms and low frequency heart rate variability in 17 patients with depression following training in Iyengar yoga (6). The present study was designed to compare responses of the EP and ML groups to a 1 week yoga program, based on psycho-physiological variables, as well as their self rated indicators of distress.