PHYSIOLOGY OF EXERCISE
Necessity of motion for body development
By motion (exercise) the muscles are stimulated in growth, becoming larger and more firm, thus giving strength and symmetry to the body. Food, without proper motion, will not develop muscular tissue to its highest degree. Exercise must be taken to stimulate the growth of the tissues forming the muscle-cells.
Among the benefits derived from exercise, the following may be noted:
Growth produced by exercise
First: Surplus nitrogen is usually cast from the body as waste matter when it is not deposited as muscle tissue by proper exercise. If the diet is balanced, regular exercise will add this nitrogenous substance to the muscle-cells far beyond normal growth, thus causing an actual increase in the size and the number of fibres.
Brain and nerve force increased
Second: A second benefit derived from muscle activity is the consequent change that occurs in brain and in nerve activity. There are certain cells in the brain and in the nervous system which control the movements of the muscles. When these cells are not used, they degenerate, but their use in exercise is not only beneficial in developing a well-rounded nervous mechanism, but also in strengthening the brain-cells that are used in intellectual work.