Synthesis of Yoga
The Synthesis of Yoga is Sri Aurobindo’s principal work on yoga; it is at once an examination of the traditional systems of yoga as well as a most thorough explanation of his method of Integral Yoga.
Continuing with Chapter 27 Hathayoga mid-page 532:
The basis for the higher aims of Hathayoga is a complete mastery of the body and the life and a freer and effective use of them, established upon a purification of their workings. The body becomes a perfected instrument by combined practice of Asana and Pranayama, purified from many of its disorders and fatigue, acquiring an immense power of health along with a greater longevity. “… the life energy seems to contain and possess and use the body rather than to be contained, possessed and used by it.”
There is the more important matter of the psychical and spiritual, depending on the connection between body, mind and spirit and between the gross and subtle body upon which Hathayoga stands. This comes in line with Rajayoga …