The reason you lose more weight when running for exercise has a lot to do with energy expenditure. Running often causes you to expend more energy than walking, hiking, skating, rollerblading or cross-country skiing. The more energy you expend at a given time, the more calories your body burns, which can help encourage weight loss.
Caloric Deficit
According to the National Institutes of Health, a pound of fat contains a total of 3,500 calories. Generating a deficit of this amount should then cause you to lose a pound of weight. One way to create this shortfall is to expend more energy through physical activities, like running. But you must burn more calories than you consume to lose any amount weight.
Running
The amount of energy you expend through running, however, is dictated by two factors---body weight and level of intensity. The more pounds you weigh, the more energy it takes to move the body. You also increase your energy expenditure by increasing the pace of your stride. Both factors have a direct impact on calories burned, thereby affecting weight-loss results.
Calories Burned
Running at a pace of 5 miles per hour can cause you to burn almost 600 calories in an hour at a weight of 155 lbs., which can translate into 1 lb. of weight loss every six days. Someone weighing 185 lbs., however, can see greater results, since this pace can burn 710 calories in the same amount of time. In this situation, running an hour a day can bring about 1 lb. of weight loss every 5 days.
Increasing the intensity of your run to 6 mph, which is about a 10-minute mile, increases your burn rate to 744 calories per hour at a weight of 155 lbs. and 888 calories per hour at a weight of 185 lbs. Now, you're looking at a weight loss of 1 lb. every 5 days and 4 days, respectively.
Diet
Not everyone is at the fitness level to run at this pace or duration each day of the week, so you may also want to include some dietary changes to encourage weight loss. Reducing your caloric intake, according to Dr. Donald Hensrud, a preventive medicine specialist with the Mayo Clinic, may actually promote better weight loss results than exercise. To do this, reduce the size of your portions as well as add healthier foods, such as fruits and vegetables, into your diet.
Member Comments