74 CONSCIOUS NERVOUS OP K RATIONS 



becomes perceptibly smaller, and, of course, weaker than 

 its fellow. 



97. Exercise is indispensable to health of muscles. 

 Growing children need much active exercise for develop- 

 ing and hardening the muscles, and all healthy children 

 crave it. Nothing is better than running and walking for 

 promoting the growth of the muscles, for developing the 

 power of the lungs and the heart, and so for aiding both 

 the free circulation of the blood and its purification, by 

 means of which the nutrition of the whole body is stimu- 

 lated. Those who exercise much in the open air (which 

 is always best) have, as a rule, good appetites, for food 

 is needed to repair the waste caused by the exercise. 



Many diseases are prevented, and some are cured, by 

 suitable exercise. A brisk walk of several miles taken 

 regularly every day would alone do much to keep the 

 whole body in normal condition. If it is impossible to 

 go out of doors for the needful amount of exercise, the 

 indoor conditions should be as nearly as possible like 

 those without. Fresh air and light should be freely 

 admitted to the rooms used, additional clothing being 

 put on when necessary. 



Rowing, swimming, boxing, horseback riding, climbing, 

 sweeping, cycling, etc. are of value in strengthening the 

 muscles of the limbs, chest, and back. A large, strong 

 chest, wherein the lungs have plenty of room for an abun- 

 dance of pure air, is not likely to belong to a consumptive 

 person. 



It is desirable that exercise should be chosen which 

 develops both sides of the body. Throwing a ball with 

 one hand, if indulged in to excess or without sufficient 

 exercise of other sorts, sometimes causes irregular devel- 

 opment of the body, and curvature of the spine may fol- 



