The Science of Yoga: The Risks and the Rewards is a 2012 non-fiction book by William Broad.
Broad investigates the veracity of health claims associated with yoga as exercise, using scientific methods.
[1] The book reviews existing scientific literature, evaluating the quality and methodology of studies related to each claim.
[1] Broad examines the historical roots of yoga in ancient India.
This historical perspective contrasts with the modern perception of yoga as primarily a wellness activity in Western societies.