He was the founder of the Progressive Muscle Relaxation and of Biofeedback.
(2001) The Physiological Correlates of Kundalini Yoga Meditation: A Study of a Yoga Master, Appl Psychophysiol Biofeedback, Jun 2001; 26(2): 147 - 53, PubMed Abstract PMID 11480165.
The books included New Mind New Body, with a foreword from Hugh Downs, and Stress and the Art of Biofeedback.