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Our Surroundings 



of the trunk and neck. This is necessary to hold the head and 

 body in an erect position. Contraction of these muscles affects 

 the process of respiration unfavorably, which in turn interferes 

 with the normal heart action and causes the breathlessness often 

 troublesome to runners. Although running will develop lung, 

 heart, and leg power better than any other form of exercise, there 

 is always present the possibility of serious injury, especially in 

 contests that demand continuous effort for any length of time. 



REGULAR EXERCISE BUILDS HEALTHY BODIES 



Brown Brothers. 



Swimming is a valuable form of exercise, as it calls into 

 action all the muscles of the body, teaches self-reliance, and pro- 

 motes courage. It also has a practical use because the ability 

 to swim often means the saving of persons from drowning. Swim- 

 ming, of course, is not the only kind of exercise that calls all 

 the muscles of the body into action. Football, golf, baseball, 

 skating, tennis, horseback riding, and military drill do the same. 

 Exercises like rowing, paddling, bowling, and shooting are espe- 



