Yoga’s great for flexibility and relaxation; but most yoga poses can be classified only as “light intensity physical activity”—the same as hanging laundry, says a recent study in Medicine & Science in Sports & Exercise.

Yes, a few poses—sun salutations, standing bows, triangles—are more vigorous, says lead study author D. Enette Larson-Meyer, Ph.D.: "For more intensity, find a faster-paced session that features those," she says. "But it won’t have the intensity of an aerobic activity like running."

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