To combat stress, many people turn to meditation or other mental stress reduction tools. But stress also creates physical response in the body and, as such, can be managed with exercise -- in particular, with yoga.
"Stress sends the entire physical system into overdrive," says Garrett Sarley, president and CEO of the Kripalu Center for Yoga & Health in Lenox, Mass. "The muscles tense, the heart beats faster, breathing patterns change, and if the cause of stress isn't discontinued, the body secretes more hormones that increase blood sugar levels, raising blood pressure. Yoga is one of the few stress-relief tools that has a positive effect on all the body systems involved."
Recognizing the detrimental effects of stress, especially in the area of heart disease, the preventive and rehabilitative cardiac center at Cedars-Sinai Medical Center in Los Angeles began offering yoga to their patients more than 10 years ago.
"Over the years, yoga has become one of our primary therapies for stress management," says C. Noel Bairey Merz, M.D., director of the preventive and rehabilitative cardiac center at Cedars-Sinai Medical Center.
Yoga-based guided relaxation reduces sympathetic activity judged from baseline levels.
35 male volunteers whose ages ranged from 20 to 46 years were studied in two sessions of yoga-based guided relaxation and supine rest. Assessments of autonomic variables were made for 15 subjects, before, during, and after the practices, whereas oxygen consumption and breath volume were recorded for 25 subjects before and after both types of relaxation. A significant decrease in oxygen consumption and increase in breath volume were recorded after guided relaxation (paired t test). There were comparable reductions in heart rate and skin conductance during both types of relaxation. During guided relaxation the power of the low frequency component of the heart-rate variability spectrum reduced, whereas the power of the high frequency component increased, suggesting reduced sympathetic activity. Also, subjects with a baseline ratio of LF/HF > 0.5 showed a significant decrease in the ratio after guided relaxation, while subjects with a ratio < or = 0.5 at baseline showed no such change. The results suggest that sympathetic activity decreased after guided relaxation based on yoga, depending on the baseline levels. Psychol Rep 2002 Apr;90(2):487-94 Related Articles, Links
Swami Vivekananda Yoga Research Foundation, Chamarajpet, Bangalore, India.
