METABOLISM 19 



an individual at complete rest in bed, for not only is 

 external work reduced to a minimum thereby, but heat 

 loss is also greatly curtailed. In these circumstances 

 the total turnover of energy is probably not more than 

 1,600 Calories per day in the case of an average patient, 

 an amount which could be supplied by 4 pints of milk. 

 If, on the other hand, a patient is allowed merely to be 

 up and moving about in the ward without doing any 

 real work, his turnover of energy is at once increased 

 about 10 per cent. It will readily be understood from 

 this how great an aid complete rest in bed is in cases in 

 which it is important to reduce a patient's expenditure 

 of energy to its lowest terms.* 



* Some practical examples of the amount of energy expended 

 in different forms of exertion may be of interest. E.g. y an hour's 

 saunter consumes 137 Calories, or about \ ounce of fat ; an hour's 

 quick walk consumes 260 Calories, or 1 ounce of fat (Miiller). A 

 walk of four miles increases the expenditure of the body by about 

 275 Calories, which could be covered by the consumption of 1 ounce 

 of fat (Zuntz). A bicycle ride of nine and one-third miles expends 

 313 Calories of energy, or 14 ounces of fat (Zuntz). If a man of 

 70 kilogrammes weight takes to living up a stair 15 metres high, 

 and goes up four times a day, he does 4,200 kilogrammes of work 

 daily ; but, as only 30 per cent, of the energy he expends actually 

 goes in doing the work, the increase in his metabolic turnover really 

 amounts to 14,000 kilogrammes, or 32'9 Calories daily. This equals 

 3 '54 grammes of fat per day, or about 4 pounds of adipose tissue 

 per year (von Noorden). 



Climbing expends twenty times more energy than walking on the 

 level ; i.e., to lift one's weight one mile in a day is equivalent to a 

 walk of twenty miles. 



A man walking against a strong wind for a mile expends an 

 amount of energy which would have raised him 8,202 feet, at a 

 cost of 1,200 Calories (about 4J- ounces of fat). 



Twelve per cent, more energy is expended when standing at 

 attention than when standing at ease (Muller). 



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