This book continues to serve as excellent resources for those interested in the study of Hatha yoga. Hatha yoga is the physical part of yoga practice and is beneficial to the body both mentally and physically. It reduces stress, rejuvenates us and improves circulation. Yoga may be as effective as or better than exercise at improving a variety of health-related outcome measures. Certain yoga asanas, if practiced regularly, are known to have beneficial effects on human body. These yoga practices might be interacting with various somatic and Neuro-endocrine mechanisms bringing about therapeutic effects. The overall performance is known to be improved by practicing yoga techniques and their effects on physical functions were reported. Yoga practices can also be used as psycho-physiological stimuli to increase the secretion of melatonin which, in turn, might be responsible for perceived well-being. This book is a major impact to current yoga and health studies. This book gives a brief outline and provides a context to assess the effects of selected asanas in hatha yoga on peak expiratory flow rate, vital capacity and speed of movement.