Muscle strength. In a 2006 study published in Alternative Therapies in Health and Medicine, Stanford University researchers reported benefits of T'ai Chi in 39 women and men, average age 66, with below-average fitness and at least one cardiovascular risk factor. After taking 36 T'ai Chi classes in 12 weeks, they showed improvement in both lower-body strength (measured by the number of times they could rise from a chair in 30 seconds) and upper-body strength (measured by their ability to do arm curls).
In a Japanese study using the same strength measures, 113 older adults were assigned to different 12-week exercise programs, including T'ai Chi, brisk walking, and resistance training. People who did T'ai Chi improved more than 30% in lower-body strength and 25% in arm strength — almost as much as those who participated in resistance training, and more than those assigned to brisk walking.
"Although you aren't working with weights or resistance bands, the unsupported arm exercise involved in T'ai Chi strengthens your upper body," says internist Dr. Gloria Yeh, an assistant professor at Harvard Medical School. "T'ai Chi strengthens both the lower and upper extremities and also the core muscles of the back and abdomen."
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No pain, big gains.
T'ai Chi is a simple and gentle physical exercise. We work at keeping
weight underside, that is, relaxing the body, stretching it, while letting gravity pull us down naturally.
Sometimes we are so tense that our shoulders rise up, for example. In
T'ai Chi practice, we release that tension consciously so that our body settles down, and we see our shoulders lower as a result.
Moving in the form, or even standing in a posture, with weight underside in our body is akin to lifting dumbbells or barbells, and such natural resistance in
T'ai Chi is what builds muscle strength that the above studies found among older adults.