Autonomic Functions In Raja-yoga Meditators.

Stress, an inevitable and constant feature throughout the lifetime, induces autonomic dysfunctions, for which meditation is considered to be an antidote. So the case control study was planned including 50 Raja-yoga meditators practicing meditation for 5 years and 50 age matched non-meditators. Autonomic function tests were performed and results were compared using the Student- t test. Mean values of resting HR, SBP and DBP were less in meditators. Galvanic Skin Response in meditators was significantly more (p<0.001). Mean increase BP response to Hand Grip Test and Cold Pressor Test was significantly less in meditators than non-meditators (p<0.001). Standing: Lying ratio, Valsalva ratio, Inspiration: Expiration ratio and 30:15 ratios were significantly increased in meditators than non-meditators. From the results, there was shifting of the autonomic balance to parasympathetic side in Raja-yoga meditators, which suggests its utility to combat the ill effects of stress.

Effect of yoga on cardiovascular system in subjects above 40 years.

This study was conducted to examine the effect of yoga on cardiovascular function in subjects above 40 yrs of age. Pulse rate, systolic and diastolic blood pressure and Valsalva ratio were studied in 50 control subjects (not doing any type of physical exercise) and 50 study subjects who had been practicing yoga for 5 years. From the study it was observed that significant reduction in the pulse rate occurs in subjects practicing yoga (P<0.001). The difference in the mean values of systolic and diastolic blood pressure between study group and control group was also statistically significant (P<0.01 and P<0.001 respectively). The systolic and diastolic blood pressure showed significant positive correlation with age in the study group (r1 systolic= 0.631 and r1 diastolic = 0.610) as well as in the control group (r2 systolic = 0.981 and r2 diastolic = 0.864). The significance of difference between correlation coefficient of both the groups was also tested with the use of Z transformation and the difference was significant (Z systolic= 4.041 and Z diastolic= 2.901). Valsalva ratio was also found to be significantly higher in yoga practitioners than in controls (P<0.001). Our results indicate that yoga reduces the age related deterioration in cardiovascular functions.