He is a proponent of the alternative medicine concept of "wellness", originally proposed in 1961 by Halbert L. Dunn, and has written books on the subject.

[2] Travis earned his BA from College of Wooster in 1965, followed by an MD from Tufts University School of Medicine in 1969,[3] and spent six years as a commissioned officer in the United States Public Health Service.

This utilized a whole-person model, based on a "Wellness Energy System" that comprised 12 dimensions, incorporating nutrition, exercise, stress, and the social environment.

[13] He contends that medicine typically treats injuries, disabilities, and symptoms, to bring the individual to a "neutral point" where there is no longer any visible illness.

[16] The Illness-Wellness Continuum proposes that individuals can move farther to the right, towards greater health and wellbeing, passing through the stages of awareness, education, and growth.

For example, a person who demonstrates no symptoms of disease, but is constantly complaining, will be facing the left side of the Continuum and away from a state of high-level wellness.

The Illness-Wellness Continuum has been viewed as promoting preventive treatment, which improves wellbeing before an individual presents with signs or symptoms of illness, as well as educating people to be aware of and avoid risk factors, in order to protect against pathology and premature death.

[20] Since then the concept has been applied to fields such as medicine,[21][22] nursing,[23][24][25] counseling, physical therapy,[12][19][26] public health,[13] and organizational development.