BONES, MUSCLES, EXERCISE, AND BEST. 303 



by a corresponding languor, but sometimes by serious injury 

 to the constitution. We are sometimes told by men that, 

 since they strained themselves by lifting, or running, or by 

 violent working at a fire, or some other occasion, they have 

 not enjoyed their former health, nor have been able to work 

 with their former energy. These evil consequences more 

 frequently follow the excessive efforts of boys and young 

 men. Dr. Hope says, that violent corporeal efforts, of every 

 description, accelerate the circulation, and cause an unnatural 

 pressure of blood upon the heart. " In growing youths, ex- 

 cessive rowing is one of the most efficient causes of this 

 disturbance of the heart. Violent gymnastics produce the 

 same effect."* 



700. The natural exercises of children, their sports and 

 games, which they enter upon and go through with boisterous 

 zeal, give them light, and varied, and sufficient muscular 

 action. None of the muscles are tasked too much, none 

 called to labor for any length of time. Children and youth 

 are not made for hard labor ; whatever work is required of 

 them should be light, varied, and short. Great exertion 

 during the forming and growing period would very soon ex- 

 haust their strength, and, if continued, it would prevent the 

 full development and growth of the muscular system, and 

 even wear down the constitution. 



701. A man does not reach his full measure of strength 

 and power of endurance until he has passed his 25th year. 

 And if, under that age, he is exposed to the hard -labor and 

 privations which older men seem to endure with impunity, 

 and in situations where can be no relaxation nor favor shown, 

 the health and strength of the youth fail ; and, if there is 

 danger from the labor and exposure, the youth is the first to 

 die. Young soldiers sink under the labors and privations of 

 the camp sooner than mature men. Napoleon complained 

 that boys were sent to supply his army, rather than men who 

 could endure the toils and the sufferings of the campaign. 



* Diseases of the Heart, Part III. Chap. 1. 



