Although a large part of the appeal of yoga is its ability to help practitioners be more in touch with their inner selves, it's no secret that it's also a great workout that strengthens, tones and improves different parts of the body. In this video, instructor Wai Lana, who hosts a popular yoga show on PBS, takes viewers through more than 15 different &NFi;asanas&NFi_;, or postures, that build muscles from top to bottom.