REVIEW OF YOGA TRAINING STUDIES CONDUCTED AT JIPMER

PROF. MADAN MOHAN
Director-Professor & Head, Department of Physiology, JIPMER, Pondicherry, India

In a study on the effect of slow and fast pranayamas on cardiovascular and respiratory parameters of school children (n = 30), we have found that slow pranayama training reduces the resting systolic pressure, diastolic pressure, mean pressure, heart rate and rate- pressure product. On the other hand, these parameters are increased by fast pranayams. Although respiratory pressures and breath holding time where increased by both types of pranayams, this increase was significant only after slow pranayam training. It was concluded that physiological effects of slow and fast pranayams are different. To study if shavasan training of very short duration can modulate physiological response to stress produced by cold pressor test and the possible mechanisms involved, we gave one week shavasan training to 10 adult volunteers (23-33 yr). There was a significant decrease in resting heart rate, diastolic pressure and rate-pressure product. Cold pressure- induced increase in these parameters was blunted after shavasan. It was concluded that shavasan training of one week duration enhances parasympathetic activity, blunts sympathetic activity, reduces load on the heart and therefore, enhances one's ability to withstand stressful stimuli. In another study on hypertensive patients, we found that yoga relaxation training of 4 weeks duration reduces autonomic reflex regulations of these patients. There was also decrease in drug dosage and improved sense of well being. In an another study on the effect mukha bhastrika on reaction time of 22 healthy school boys, we have found that 9 rounds of mukha bhastrika produces an immediate and significant decrease in visual as well as auditory reaction times. A decrease in reaction time indicates an improved sensory-motor performance and enhanced processing ability of the central nervous system. This may be due to a greater arousal, faster rate of information processing and improved concentration. Our observations have applied value in situations requiring faster reactivity such as sports, race driving, machine operation and specialized surgery.

NEUROPHYSIOLOGICAL CORRELATES OF PHASES OF
MEDITATION [DHARANA, DHYANA AND SAMADHI]

NAVEEN K. VISWESWARAIAH, B.N.Y.S., Ph.D.
Asst. Prof., Division of Yoga & Life Sciences,
Swami Vivekananda Yoga Research Foundation, Bangalore, India

Meditation is a state of consciousness featured by deep relaxation and internalized attention. Traditionally, there are three different phases in meditation i.e., focusing (dharana), effortless mindfulness (dhyana) and a state of transcendence (samadhi). Different meditation techniques exist and their physiological effects have been studied using a range of variables. Based on their characteristics these meditation techniques can be categorized as one of the traditional phases (i.e., dharana, dhyana,or samadhi). For example, Brahmakumaris Raja Yoga meditation and Zen meditation emphasize the dharana phase, transcendental meditation (TM) and meditation on a syllable OM can be categorized as dhyana type of meditation. Theoretically, the end phase of all types of meditations is transcendence (samadhi). Based on the available literature TM came to be described as a 'wakeful hypo-metabolic physiologic state', whereas Brahamakumaris Raja Yoga meditation and OM meditation showed differential activity in the different subdivisions of the autonomic nervous system, some characteristic of 'activation' and others of 'reduced arousal'. The neurophysiological correlates of each of the states will be described.