Using the StairMaster at a medium pace burns 5 calories every minute for a person weighing 120 pounds. For the same energy exerted, each additional 30 pounds a person weighs burns an additional 2 pounds. More calories are burned if the exertion is greater or the person weighs more.
According to Mayo Clinic, The StairMaster burns up to 819 calories hourly. This is four times the calories burned through general cardiovascular exercise. This choleric burn is attributed to the front muscle usage in the thighs (quadriceps) as well as the buttocks, which balances the body's mass against gravity's force to generate a vigorous workout.