Asthma. At the Northern Colorado Allergy Asthma Clinic in Fort Collins, a controlled clinical study of university students (19 to 52 years old) with asthma concluded that yoga techniques seem beneficial as an adjunct to the medical management of asthma, according to the 1998 published abstract. Using a set of asanas, pPranayama, and meditation, the yoga group practiced three times a week for 16 weeks. Though pulmonary functions did not show a significant variance between yoga and control groups, "analysis of the data showed that the subjects in the yoga group reported a significant degree of relaxation, positive attitude, and better yoga exercise tolerance. There was also a tendency toward lesser usage of beta adrenergic inhalers."
Cardiovascular Risk Factors. A three-month residential study treating patients with yoga, meditation, and a vegetarian diet at Hanover Medical University in Germany found a substantial reduction in risk factors for heart disease (including blood pressure and cholesterol) in participants, according to an abstract published in Acta physiologica Scandinavica Supplementum in 1997.
Carpal Tunnel Syndrome. A randomized, single-blind, controlled clinical trial at the University of Pennsylvania School of Medicine in Philadelphia concluded, "In this preliminary study, a yoga-based regimen was more effective than wrist splinting or no treatment in relieving some symptoms and signs of carpal tunnel syndrome." The study, published in the Journal of the American Medical Association in 1998, also noted that "Subjects in the yoga groups had significant improvement in grip strength and pain reduction, but changes in grip strength and pain were not significant for control subjects."
Arthritis. Also at the University of Pennsylvania School of Medicine, a yoga-treated group with osteoarthritis of the hands improved significantly more than the control group in "pain during activity, tenderness, and finger range of motion." The randomized controlled clinical trial, published in the Journal of Rheumatology in 1994, concluded, "This yoga-derived program was effective in providing relief in hand osteoarthritis. Further studies are needed to compare this with other treatments and to examine long-term effects."
Researchers have also evaluated effects of yoga on healthy adults and in athletes and compared the effects of yoga to the effects of other forms of physical exercise. One study conducted at the Government Vemana Yoga Research Institute in Secunderabad, India, focused specifically on athletes practicing pranayama techniques. After two years of observation and testing, according to the report published in the Indian Journal of Medical Research in 1994, "the results...showed that the subjects who practiced pranayama could achieve higher work rates with reduced oxygen consumption...and without increase in blood lactate levels." According to Mary Pullig Schatz, M.D., author of Back Care Basics: A Doctor's Gentle Yoga Program for Back and Neck Pain Relief (Rodmell, 1995), the study results indicate that in the pranayama subjects, the body is using oxygen "more efficiently (aerobically) rather than shifting to less-efficient anaerobic (lactate-producing) metabolism."