Basal metabolic rate
As we all know to lose weight we need to make sure our energy consumed (calorie intake), is less that our calorie output (exercise).
Obviously our bodies need energy to keep going, but so many of us really do consume many more calories than needed.
When you are ready to go on a healthy weight loss journey, you will find that most eating plans work from a 1200 calorie day base diet.
Yes this is a good rule of thumb, but there is a way of measuring your basal metabolic rate (BMR) to be more precise to you. BMR is the energy of a person measured in the fasting state, completely at rest in a control environment. BMR is the amount of energy your body uses in order to survive. It takes in the energy expenditure due to involuntary muscle contraction such as the beating of the heart and movements of your bowels and gastrointestinal tract.
Look at the table below to work out what your BMR should be. This means what your base calorie consumption should be.
| Age range (years) | Equation for BMR k/cal per day | |
| Males | 10-18 18-30 30-60 Over 60 |
(17.5 x wt) +651 (15.3 x wt) +679 (11.6 x wt) +879 (13.5 x wt) +487 |
| Females | 10-18 18-30 30-60 Over 60 |
(12.3 x wt) +746 (14.7 x wt) +496 (8.7 x wt) +829 (10.5 x wt) +596 |
Weight is to be in kilograms.
Example calculation: I am 42 years old with a body weight of 66kg, my BMR is 1403 kCal/day ((8.7 x 66) + 829 = 1403.
Source: Whintey and Rolfes, Understanding nutrition, 1996
I would use this as a guide, and if you are trying to lose weight, I would still only consume 1200 – 1300 k/Cal per day. Ignore the amount of exercise (calorie burnt), because if you keep eating back what you have burnt off, you will remain the same. I find many people use the “been to the gym today so I can eat this cake now” excuse, but you cannot do this if you are wanting results.
There are many factors that can alter the BMR.
The BMR can be higher in tall thin people, children and pregnant women, stress, certain drugs and if unwell – fever.
BMR is lowered in fasting or starving situations and both in heat and cold temperature.
Note: hormones (thyroid) can alter this as well. BMR is lowest when sleeping.
