You may consider calories the enemy, but calories in food are there to provide your body with the energy it needs to maintain basic functions such as breathing, blood circulation and brain activities. The only problem with calories is when you eat too many. Eating more calories than your body needs leads to weight gain, and all the possible problems associated with carrying around excess weight such as heart disease and type 2 diabetes. Knowing how many calories you burn in a day can help you balance your calorie intake to maintain your weight.
Convert your height and weight into metric measures. Divide your weight in pounds by 2.2 to determine your weight in kilograms. Multiply your height in inches by 2.54 to determine your height in centimeters.
Calculate your resting energy exenditure, or REE. The REE is a mathematical formula that estimates the number of calories you need to maintain your temperature and basic body functions. REE calories for women = 655.1 + (9.65 x wt in kg) + (1.84 x height in cm) + (4.68 x age in years).
Determine your activity factor. If you live a sedentary lifestyle, meaning you spend most of your day reading or watching television, your activity factor is 1.3. Women who exercise at a moderate-intensity, walking at a rate of 2.5 mph one hour a day, have an activity factor of 1.5. If you work out a little harder, walking at a pace of 3.5 mph, your activity factor is 1.6. Women who participate in team sports have an activity factor of 1.9, and full-time athletes that workout strenuously each day have an activity factor of 2.2.
Multiply your REE by your activity factor. This number is the number of calories you burn each day.