Humphrey served as Director of Health and Physical Education for Bedford, Ohio City Schools.
In 1951, he became Assistant Professor of Health and Physical Education at Michigan State University, holding the position for two years.
Humphrey wrote many textbooks, children's books, articles, and research reports in the field of physical education.
Humphrey's research was focused in the area of child education through motor activity.
Through his research, he developed the AMAV Technique, a procedure for teaching reading through movement.