176 PHYSIOLOGY AND TEMPERANCE. 



with larger quantities of oxygen. Walking is one of the 

 best exercises we can get, because it involves the use of a 

 great many muscles. The legs, arms and body are all in 

 motion, which means muscular action. Swimming is another 

 form of exercise which is especially useful, inasmuch as it 

 requires the active employment of a very large number of the 

 muscles. A healthy, strong person in water of a moderate 

 degree of warmth, so that too much heat of the body is not 

 carried off, will, after a little practice, not only secure all 

 the benefits of a bath, but also the good effects of the 

 most perfect natural exercise. The feeling of comfort and 

 general toning of the system after a good swim can hardly 

 be obtained in any other way. 



But useful as are these natural forms of exercise, and each 

 commendable for some special feature, yet no single one of 

 them calls into action all the voluntary muscles; hence, in 

 addition to these, it is advisable, especially during the period 

 of growth and development, -to devote a certain time daily 

 to artificial training of the muscles. 



3. Regulation of Exercise. The kind of exercise most 

 beneficial depends upon the age, the condition of health, and 

 to a certain extent the sex and the occupation. Exercise in 

 health may with advantage be carried to slight weariness, 

 but not so as to cause a feeling of prostration. 



The employment of some affords ample exercise for the 

 well-being of the body. The occupation of others is such 

 that only a portion of the muscular system is engaged. In 

 these the idle muscles should be exercised in other ways. 

 The brain -worker needs exercise of the whole muscular 

 system, and, when practicable, it should be varied from 

 day to day. 



Exercise should be taken in the open air. As we have 

 said, it is not the muscles alone that are benefited. The 

 various organs are made to do more work. The action ot 



