According to the HealthStatus.com Calorie Burn Calculator, an average 150-pound person burns 3,500 calories when running at a pace of 6 mph for approximately five and a half hours. A heavier person burns more calories doing the same activity.
Individualized calorie burn is determined by using formulas that fact the person's weight, age and the metabolic equivalent value of the activity. The National Cancer Institute provides a list of metabolic equivalent values for common activities. The use of an online calculator or mobile phone application may help determine a person's calorie burn based on the personal information inputted by the individual.