PHYSIOLOGY OF STRENGTH AXD ENDURANCE. 189 



tions, the muscle will then liberate energy for a long time. This 

 latter condition is what we call endurance. 



The power and endurance of the human machine is limited 

 according to our understanding of the above facts, and also our 

 recognition of its slowness in getting started. Like any other pon- 

 derous and intricate machine, the bodv requires time to get in 

 harmonious working order. The brain, nerves, heart, and skeletal 

 muscles must be given some warning of the work they are expected 

 collectively to perform. Ignorance of this fact has broken down 

 many a young man who aspired to honors on the cinder path. The 

 necessity of getting all the parts of the body slowly in working order 

 is well understood by trainers and jockeys on the race track, as is 

 evidenced by the preliminary " warming up " they give their horses, 

 although it is doubtful if the trainers could give any physiologic rea- 

 son for this custom. 



Of the substances supplied to the muscle by the blood, oxygen 

 is one the want of which is soonest felt. The muscle contains within 

 itself a certain store of oxygen, but one which is by no means equal 

 to the oxidizable substances. The muscle's activity is dependent to 

 a great extent on the character and force of the blood flow through 

 the muscle. It must be clear of the waste products, as well as con- 

 taining sufficient oxygen to continually keep up a renewal of energy. 

 From what has been said it will readily be seen that the result of a 

 muscular task which an athlete wishes to perform will depend pri- 

 marily on his muscular bulk and on the condition of these muscles, 

 and the rate at which he expends his capital; the test of his endurance 

 will depend upon the condition of the other parts of his body, and 

 how thoroughly and rapidly they will carry off the quickly formed 

 poisonous products and supply fresh ones. 



ISTineteen pugilists have died in the ring the last seven years. 

 Not one of these deaths was directly due to the force or severity of 

 the blows struck, but because the fighters were " out of condition." 

 The waste products caused by the rapid muscular work accumulated 

 in their bodies, and, forced to go on with their exertion, they dropped 

 exhausted to death — poisoned by material of their own manufacture. 

 Less attention paid to mere muscular exercise, and more to the con- 

 dition of the blood and other parts of the human machine, would 

 have brought different results. These facts impressed upon a cer- 

 tain class of athletes would be of great moral and social advantage to 

 the world in general. It means that these individuals must have 

 fresh air to live in, clean skins, good, substantial food, a fixed num- 

 ber of hours for sleeping, and avoidance of stimulants. If it was 

 well understood that no man could go into the exhibition ring, or 

 into any contest requiring physical exertion, unless he could show, 



