Experts Say Yoga the Key to Health, Rapid Weight Loss
A recent randomized, controlled, six-month trial of yoga practice among healthy seniors found significant benefits in physical health but no improvement in cognitive tests. It appears that a regular practice of hatha yoga does result in better health and even weight loss, the researchers found.
Yoga is a commonly practiced, mind-body approach that has components centering around meditation, breathing, and activity or postures. In recent US surveys of adults, 7.5% reported having used yoga at least once in their lifetime and 3.8%–5.1% reported having used it in the previous 12 months.1,2 Iyengar yoga, one of the active, or Hatha, yoga techniques, is a system for developing physical and mental well-being through stretching of all muscle groups for strength, flexibility, and physical balance. A person assumes a series of stationary positions that use isometric contraction and relaxation of different muscle groups to create specific body alignments. There is also a deep relaxation component. Iyengar yoga is amenable to easy adaptation for elders through modifications of the poses and the use of props, such as blankets and chairs.
The results of the study surprised the researchers. While there was no improvement in cognitive skills among the regular yoga practitioners, there were significant gains in other measures of health.
The improvements in physical measures directly related to the yoga intervention are not surprising. Yoga practice involves training on poses very similar to these outcome measures. One-legged balance may have some health implications, such as risk of falls, and has been shown previously to be improved in healthy older people practicing tai chi, another mind-body technique of which balance exercises are a component.61,62
Though this study did show that yoga produced beneficial effects on quality-of-life measures, the mechanism of action of these improvements may not relate directly to the yoga. Socialization, placebo, and self-efficacy effects are other potential mechanisms. The exercise group controlled for socialization to some degree, but there was less of a class format in the exercise group. At least 1 previous study has suggested that exercise-related improvements in stress were secondary to class participation and not to improvements in fitness. Future yoga intervention studies will need to carefully control for the class aspect that may be beneficial to everyone, but especially seniors. There is also likely some placebo effect related to the yoga intervention. One group has already shown that psychological benefits of an aerobic exercise intervention in a group of healthy young adults could be increased simply by telling subjects that the exercise program was specifically designed to improve psychological well-being.64 The placebo effect, expectancy, and self-efficacy may have a significant impact65,66 and are difficult to adequately control for in behavioral interventions that are necessarily non-blinded. Even reported cognitive improvements related to transcendental meditation may be related to expectancy of subjects recruited for trials.