This pose is so named because it represents the leap the Hindu monkey god (Hanuman) made from the southern tip of India, as described in the epic poem, the "Ramayana."
Half monkey pose is particularly beneficial for runners as it improves flexibility in the back of the legs, particularly in the hamstrings, and opens the hips. The pose is believed to relieve sciatica pain, tone the reproductive organs, stimulate the abdominal organs, reduce stress and fatigue, improve overall balance and alignment and stretch the lower back.
Beginners, or those with limited flexibility may rest their hands on their hips or on blocks placed on either side of the front leg. They may also remain upright rather than folding over the front leg.