of uncomfortable shoes on muscular activity; mind and disposition. 4. State effect of aversion to walking on muscles; circulation. 5. If a shoe is too loose, it slips up and down at the heel and chafes the skin there; if too tight, there is pressure on the toes, which causes a corn or ingrowing nail. Have your shoes been correct, or have they been too loose or too tight? According to this test, what proportion of people wear shoes that are too tight? 6. How many sprained ankles have you known among boys; girls? 7. Why is it that people who grow up in warm climates have high, arched insteps, and short, broad, elastic feet, but people of the same race who pass their childhood in cold climates often have long narrow feet with low arches and sometimes have the deformity called "flat foot"?
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Fig. 52.—Arch of Foot. It forms an elastic spring.
Instinct as a Guide for using the Muscles.—The instinctive feeling called fatigue tells us when to rest. There is also a restless, uneasy feeling that comes over a normal human being when confinement and restraint of the muscles have reached an unhealthy limit. This feeling should not be repressed for long at a time. Many, ruled by avarice, ambition, interest in sedentary work, a silly notion of respectability, or a false conception of duty, have repressed this feeling and have lost it. There is then a feeling of languor, and a disinclination to the very activity which health demands. An unheeded instinct is as useless as an alarm clock that has been habitually disregarded.
Exercise and Climate.—In our warmest states and in the tropics, one hour's vigorous physical labor a day, combined with the ordinary activities of life, will keep a person in good condition. In the colder states, muscular exertion for several hours is needed daily.
Complete Living.—Numberless people have devoted themselves to an intellectual occupation, and planned to keep their bodies sound by gymnastics and special exercises. Because of the monotony of exercises, they are soon given up in nearly every instance. The safest way is never to allow all the energies to be devoted to a one-sided occupation, but so to plan one's life and work that a part of the time is devoted to some physical work, whether it be in a garden, workshop, or orchard; in walking a long distance to the office; at bookbinding, cooking, wood carving, or any one of various other useful occupations. The result of manual training shows that not only strength of body, but strength of mind, is promoted by physical labor. Problems of war and of the chase kept active both the body and mind of the savage. Hence he led
