Spark image

Human energy demands

How much energy do we need to take from food in each 24 W hours? The answer depends very much on the sort of people we are particularly on our age and our work.

Some needs are shown in the following table:

  Energy (kJ/day)  
CHILDREN    
0-1 year old 4200  
2-6 years old 6300  
7-10 years old 8400  
     
TEENAGERS BOYS GIRLS
11-14 years old 11500 11500
15-19 years old 14700 10500
     
ADULTS MEN WOMEN
Lying in bed all day 7400 6300
Working 8 hours per day    
     
Light work 12000 9500
Heavy work 15000 12500
Very heavy work 21000  
     
PREGNANCY    
Early months   10000
Late months   11500
Nursing the baby   12500
     
Activities kJ per minute  
Resting in bed 4  
Washing, shaving, dressing 14  
Walking 21  
Standing 7.5  
Cycling 28  
Hewing coal 28  
Loading coal 26  
Working in a mine 28  
     
Power of the heart 1W  
Power of the brain 25W  
Power of a 15 year old student 350-700W  
 
 
 
© Keith Gibbs 2020