A sedentary person is one who doesn't spend enough time being active, which according to the MayoClinic.com means completing less than two hours of moderate or 75 minutes of vigorous activity weekly. The number of calories your body burns in a sedentary state is determined by your basal metabolic rate, or BMR.
Calculate your BMR with the following formula for men from DietNation: 66 + (6.23 x weight in pounds) + (12.7 x height in inches) - (6.8 x age in year). Women should use a different formula: 655 + (4.35 x weight in pounds) + (4.7 x height in inches) - (4.7 x age in years). Multiply your BMR by 1.2 to determine your daily caloric needs in a sedentary lifestyle.
Use your BMR and daily caloric needs to plan a diet and exercise regime to help you lose, gain or maintain your weight, advises Good Housekeeping. Eat the number of calories you calculated for your sedentary needs to maintain your weight with no change in activity, or increase your activity level to help you lose weight.
A 6-foot-tall, 28-year-old sedentary man weighing 200 pounds would calculate his BMR as follows: 66 + (6.23 x 200) + (12.7 x 72) - (6.8 x 28) = 2,150 BMR. Then multiply the BMR by 1.2 to calculate 2,580 calories needed each day. A 6-foot-tall, 28-year-old sedentary woman who weighs 200 pounds would calculate her BMR as follows: 655 + (4.35 x 200) + (4.7 x 72) - (4.7 x 28) = 1,731 BMR. 1,731 times 1.2 = 2,077 calories needed each day.