CHAPTER XXXVI 

 HYGIENE OF THE CIRCULATORY SYSTEM 



220. Care of the heart. Every contraction of the ventricles 

 (the two ventricles work together) sends a wave of pressure 

 through the blood in the arteries. The muscular and elastic 

 walls of the arteries " give " somewhat to this pressure, and 

 this is the pulse which can be felt in any artery near the sur- 

 face of the body, as at the wrist, on the temples, or immedi- 

 ately in front of the ear. From the character of the pulse the 

 physician can often tell a great deal about the workings of 

 the heart and about the condition of the blood vessels. The 

 pulse may be regular or irregular ; it may be strong or weak. 



A strong heartbeat would ordinarily increase the pressure 

 of the blood inside the arteries ; but if the arteries are flabby, 

 the additional work of the heart may fail to distribute the 

 blood properly to all parts of the body. Cold feet and hands 

 are an indication of inadequate circulation, but the cause of this 

 condition may be in the heart or it may be in the blood vessels. 



In examining a person the careful physician, athletic direc- 

 tor, or insurance examiner will always listen to the beating of 

 the heart and examine the pulse and test the blood pressure. 

 From the sounds of the heart he can tell whether there is a 

 defect in any of the valves. A leaky heart has to do a great 

 deal more pumping to keep the body supplied than a sound 

 heart, since a portion of every stroke is wasted in pumping 

 blood that goes back into the auricles. 



A weak heart usually shows itself in breathlessness. If you 

 cannot climb stairs, or take a brisk walk, or play a lively 

 game, without getting out of breath, the trouble is more likely 

 with your heart than with your lungs. In training for athletics 



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