others suffer the penalties of feebleness, a lower standard of functional
activities, and premature decay, the fortunate possessor of a sound mind
in a sound body is better prepared, with proper application, to endure the
hardships and win the triumphs of life[13].

This element of physical capacity is as necessary to a useful and
energetic life, as are mental endowment and intellectual acquirement.
Instinct impels us to seek health and pleasure in muscular exercise. A
healthy and vigorous child is never still except during sleep. The
restless limbs and muscles of school children pent up for several hours,
feel the need of movement, as a hungry man craves food. This natural
desire for exercise, although too often overlooked, is really one of the
necessities of life. One must be in ill health or of an imperfect nature,
when he ceases to feel this impulse. Indeed, motion within proper bounds
is essential to the full development and perfect maintenance of the bodily
health. Unlike other machines, the human body becomes within reasonable
limits, stronger and more capable the more it is used.

As our tenure of life at best is short, it is our duty to strive to live
as free as possible from bodily ills. It is, therefore, of paramount
importance to rightly exercise every part of the body, and this without
undue effort or injurious strain.

Strictly speaking, physical exercise refers to the functional
activity of each and every tissue, and properly includes the regulation of
the functions and movements of the entire body. The word exercise,
however, is used usually in a narrower sense as applied to those movements
that are effected by the contraction of the voluntary muscles.

Brief reference will be made in this chapter only to such natural and