Here's a short passage from 1937 on exercise cults and fads and how they related to exercise fads and gadgets and exercising to get muscles strong--or living in such a way that produces whole health and well-being.
Source: "Exercise and Health" by Jesse Feiring Williams, A.B., M.D.; Professor of Physical Education, Teachers College, Columbia University; National Health Series; Edited by the National Health Council (1937).
*Photo by Ron Jones