FOOD 345 



The energy required for various degrees of exercise are shown 

 below and one can compute the number of calories used per day 

 by multiplying the calories per hour by the hours of each kind of 

 exercise per day. Do this and see how near it comes to the esti- 

 mate for a person of your age in Table I. 



TABLE II 

 AVERAGE NORMAL OUTPUT OF HEAT FROM THE BODY 



Average 

 Conditions of Muscular Activity Calories 



per Hour 



Man at rest, sleeping 65 calories 



Man at rest, awake, sitting up 100 calories 



Man at light muscular exercise 170 calories 



Man at moderately active muscular exercise 290 calories 



Man at severe muscular exercise 450 calories 



Man at very severe muscular exercise 600 calories 



Food Proportions. In order that the body may have tissue 

 building foods and fuel foods in healthful proportions, we ought 

 to eat from two to three ounces of proteid per day, and enough 

 fats and carbohydrates to make up the number of calories which 

 we may require as indicated above. 



Since the fuel value of carbohydrates is only | to J that of fats, 

 our diet should have two or three times as much carbohydrate, 

 especially in warm weather, when the concentrated fuel of the fats 

 is less needed. Still another way of reaching the same result is 

 to take sV ounce of proteid for each pound of our weight, and enough 

 of the fuel foods (fats and carbohydrates) to make up the re- 

 quired number of calories, for energy production. This makes a 

 diet rather low in proteid especially for growing children, but our 

 usual mistake is to use too much, rather than too little proteid, 

 and one good authority sets the amounts even lower. 



A safe proportion for growing boys and girls would be about 

 2 or 2J ounces of proteid per day, and enough fuel foods to supply 

 the required energy, which will depend upon the age and activity 

 as already stated. 



