J10 THE HOME, FARM AND BUSINESS CYCLOPEDIA. 



EXEECISE. 



The constitution of external nature shows that man was destined for an 

 active existence, as, without labour, scarcely any of the gifts of providence 

 are to be made available. In perfect harmony with this character of the 

 material world, he has been furnished with a muscular and mental system, 

 constructed on the principle of being fitted for exertion, and requiring ex- 

 ertion for a healthy existence. Formed as he is, it is not possible for him 

 to abstain from exertion without very hurtful consequences. 



MUSCULAR EXERCISE. With regard to merely bodily exercise, it is to 

 be observed, in the first place, that we have no fewer than four hundred 

 muscles, each designed to serve some particular end in locomotion or in 

 operating upon external objects. A sound state of body depends very 

 much upon each of these muscles being brought into action in proper cir- 

 cumstances and to a suitable extent, There is even a law operating within 

 a certain range, by which each muscle will gain in strength and soundness 

 by being brought into a proper degree of activity. 



The process of waste and renovation may be said to be always going on 

 in the body, but it does not go on with permanent steadiness unless the 

 muscular system be exercised. Whenever one of the organs is put into 

 exertion, this process becomes active, and the two operations of which it 

 consists maintain a due proportion to each other. A greater flow of blood 

 and of nervous energy is sent to the organ, and this continues as long as 

 it is kept in activity. When one state of action follows close upon ano- 

 ther, the renovating part of the process rather exceeds the waste, and an 

 accretion of new substance, as well as an addition of fresh power takes 

 place. On the contrary, when an organ is little exercised, the process of 

 renovation goes on languidly, and to a less extent than that of waste, and 

 the parts consequently become flabby, shrunken, and weak. Even the 

 bones are subject to the same laws. If these be duly exercised in their 

 business of administering to motion, the vessels which pervade them are 

 fed more actively with blood, and they increase in dimensions, solidity, 

 and strength. If they be little exercised, the stimulus required for the 

 supply of blood to them becomes insufficient ; imperfect nutrition takes 

 place ; and the consequences are debility, softness, and unfitness for their 

 office. Bones may be so much softened by inaction, as to become suscep- 

 tible of being cut by a knife. In a less degree, the same cause will pro- 

 duce languor and bad health. 



It is of the utmost importance to observe, that the exercise of any par- 

 ticular limb does little besides improving the strength of that limb ; and 



