The moon has a rich symbolic significance in yoga mythology. In hatha yoga, for example, the sun and the moon represent the two polar energies of the human body. In fact, the word hatha itself is often divided into its two constituent syllables, "ha" and "tha", which are then esoterically interpreted as signifying the solar and lunar energies respectively.
ardha = half
candra = glittering, shining, having the brilliancy or hue of light (said of the gods); usually translated as "moon"
Strengthens the abdomen, ankles, thighs, buttocks, and spine
Stretches the groins, hamstrings and calves, shoulders, chest, and spine
Improves coordination and sense of balance
Helps relieve stress