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Advantages of Work and Play over Gymnastic Exercises.—The interest that comes from doing something useful, makes muscular exertion doubly beneficial to the health. The lifting of dumbbells, Indian clubs, and pulley weights, and letting them down again, tends to become very irksome, even though done with the knowledge that the exercise will benefit the health. Useful labor and games place definite objects in view and do not require so great an effort of the will nor exhaust the nerves so much as mere exercise. The interest in the work or the game serves to arouse all the nerves and muscles to work in harmony.

Fig. 49.—Desk too Low. (Jegi.)

Fig. 50.—Correct Position.

Fig. 51.—Slipping down in Seat.

An Advantage of Gymnastics over Work and Play.—Gymnastics can furnish any required variety of exercises and can develop exactly the muscles that need development and leave those idle that have become overdeveloped by doing constantly one kind of work or playing continually the same game. The deformity of a flat chest (and round shoulders which always accompany it) does not so often indicate a weak chest or small lungs as it indicates weak or relaxed muscles of the back and the habit of sitting in a relaxed position at work (Figs. 49, 50, 51). Gymnastic