146 APPLIED PHYSIOLOGY 



The average frequency of the pulse varies with age as 

 follows : 



Foetus ... ... ... 130-140. 



0-1 year ... ... ... 130. 



1-2 years ... ... ... 115-120. 



3-4 ... ... ... 105-110. 



5-9 ... ... ... 95-100. 



9-10 90. 



16-17 80. 



Adults ... ... ... 70-80. 



In old age it tends to quicken again a little. As 

 a general rule the pulse tends to be slower in tall and 

 big men than in short and small. It is quicker in 

 women than in men. Muscular effort quickens the 

 pulse considerably; mental effort slightly. On slow 

 walking it may run up to 100 per minute, and on quick 

 walking to 150. Exposure to cold renders the pulse 

 less, and response to warmth more frequent. A cup of 

 hot milk or a plateful of hot soup raises the pulse five 

 beats for half an hour ; large quantities of cold water 

 may reduce it ten beats. Cold dry meals have no 

 influence, but warm meals result in quickening. 



Every sensation of burning, pressure or nausea in the 

 stomach or of distension in the intestine (especially 

 the rectum) raises the rate. It is in this way that 

 indigestion or flatulent distension of the bowels causes 

 * circulatory excitement ' and sleeplessness. 



The volume of the pulse, or the height to which it 

 appears to rise under the finger, indicates the increase 

 in pressure within the artery during systole, or the 



