RESPIRATION 303 



The Hygiene of Breathing. A great deal is written 

 by popular teachers of hygiene in support of habitual 

 deep breathing and the practice of special breathing 

 exercises. It is certainly desirable to be -able to breathe 

 deeply, to have a large vital capacity. It is not well 

 to fall into indolent habits which lead to the disuse of 

 many of the muscles adapted to help in inspiration nor 

 to fail to use all parts of the lungs at times. The re- 

 sistance of the lung tissue to tuberculosis and other 

 diseases is undoubtedly increased when it is well subjected 

 to mechanical movements. 



On the other hand, contrary to the usual instruction, 

 the best breathing exercises are those which are taken 

 involuntarily as a part of general muscular activity. 

 We have seen that it is possible to derange the composi- 

 tion of the blood by overbreathing. We cannot easily 

 overbreathe when a great respiratory requirement has 

 to be met, as in running or playing tennis. We may 

 breathe deeply without tending to produce acapnia if 

 we slow the rhythm of the movements at the same time. 

 Singing is an excellent exercise, demanding as it does the 

 quick, strong intake of the breath and the prolonged, 

 carefully regulated expiration. 



It has often been noted that breathing exercises have 

 well-marked mental effects. Too much has probably 

 been made of this fact and undesirable results have often 

 been spoken of as though they were to be sought for. 

 Acapnia produces mental confusion and the state has 

 been described as one of exaltation. Oriental religion- 

 ists have urged this claim upon their western disciples. 

 From a scientific standpoint it appears morbid and 

 dangerous. The mild emotional reaction of the singer 

 is as much as can safely be recommended. 



While there is no good reason to advise people to 

 breathe more deeply than their inclination suggests, 

 it is desirable to breathe from a high base-level that is, 

 with the chest well rounded even in expiration. This 

 habit, if not foolishly exaggerated, helps to maintain 



