EFFECTS OF MUSCULAR EXERCISE. 121 



CHAPTER V. 



Effects of Muscular Exercise on the principal Functions of the 

 Body explained Shampooing a Substitute for Exercise 

 Evils of deficient Exercise Best Time for taking Exeicise 

 Always to be taken in the open Air Different Kinds- 

 Walking Riding Dancin g Gymnastics Fencing Shut 

 tlecock Reading aloud Case illustrative of the Principles 

 of Exercise Involuntary Muscles. 



WE have seen that exercise is necessary for de- 

 veloping and improving the health of the muscular 

 system ; but it still remains for us to explain how it 

 acts in imparting tone and strength to the rest of the 

 body, and to mention the circumstances by which 

 its employment ought to be regulated. 



Man being intended for a life of activity, all his 

 functions are constituted by Nature to fit him for 

 this object, and they never go on so successfully as 

 when his external situation is such as to demand the 

 regular exercise of all his organs. It is, accordingly, 

 curious to observe the admirable manner in which 

 each is linked in its action and sympathies with the 

 rest. When the muscular system, for example, is 

 duly exercised, increased action in its vessels and 

 nerves takes place, as already observed ; but the 

 effect is not by any means limited to the mere organs 

 of motion. The principal blood-vessels in all parts 

 of the body lie imbedded among muscles, for both 

 the protection and aid which the latter afford them. 

 Every contraction of the muscles compresses the 

 diameter of the vessels ; and as the blood contained 

 in them cannot retrograde in its course, it is pro- 

 pelled in the arteries from the heart towards the ex- 

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