Think about it. Everything from running to weightlifting, aerobics to bicycling, emphasize the contraction of a set of muscles to the desired goal. This results in the compression of the spaces between the bones, and, with 209 bones in the body, that's a lot of spaces. But with Yoga, the postures put more of the emphasis on the expansion of the spaces between the bones, with a balanced attention to the muscles that cause that expansion. This brings an opening up of the body.
Energy flows freely.
Breathing is easier. Organs and musculature regain their normal positions and can operate more freely. And because yoga allows the participant to move at his or her own level of work, there is no competition involved. The level one works at is determined by the participant alone. So breathe in deep, you're not asleep open your mind.