How Many Calories Do You Need?

Many runners are concerned with their weight. After all, extra pounds are tough to carry on a five-mile run. This concern can lead to under-eating, which isn't any healthier than over-eating. To find the approximate number of calories you need daily, use the following three-step calculation. (Note: This is to maintain body weight.)

Step 1: Determine your Resting Metabolic Rate (RMR). This is simple: multiply your body weight by ten. If you weigh 150 pounds, 150 x 10 = 1500. So, your RMR is 1500.

Step 2: Determine your overall activity level. If you're very active, add 60% - 80% to your RMR. If you're moderately active, add 40% - 60%. And if you're generally sedentary, add 20% - 40%. We'll say our 150-pound runner is moderately active, and use the middle of the range. So 1500 + (1500 x 50%) = 1500 + 750, or 2250.

Step 3: Add your “workout calories.” Figure 100 calories per mile run - this just is an approximation. If our subject runs four miles a day… 4 x 100 = 400, and 2250 + 400 = 2650.

So, our hypothetical 150-pound runner needs about 2650 calories per day.