Katch-McArdle RMR Calculator

The estimates above are calculated using the Katch-McArdle equation, which uses lean body mass rather than total body weight to determine the amount of energy (in calories) your body needs to survive at complete rest. It may provide a more accurate estimate for athletic individuals with above- or below-average muscle mass compared to other equations such as the Mifflin-St Jeor and Cunningham equations.

Your resting metabolic rate (RMR) is the estimated number of calories your body requires each day to maintain essential physiological processes at complete rest.

Your lean body mass is determined by calculating the amount of fat in your body from your body fat % value, and subtracting this from your total body mass. It's the combined weight of all your muscles, skeleton, organs, and non-adipose tissues.

Remember:

✓ This is an estimate, not a direct measurement.

✓ Muscle mass, illness, injury and genetics can all influence your true metabolic rate.

✓ Energy requirements for training and recovery are substantially higher than your resting metabolic rate.

If you undertake ANY activity beyond laying in bed for 24hrs and breathing, your body will require more energy than your calculated resting metabolic rate.