# What Do the Elevation Levels on Treadmills Mean?

## Elevation Percentages

Treadmills depict the incline or decline of the deck as a percentage, which typically ranges from zero, when the treadmill deck is flat, to 12 degrees, when the treadmill deck is inclined to the max. Some treadmills incline at an even higher percentage, and others even have a decline feature where the percentage is displayed as a negative number. The percentage shown on the treadmill display is the grade of the treadmill deck, which isn’t the same thing as the angle of the deck. The grade is measured using a formula that considers the number of vertical rises – height of the highest point of the treadmill deck when inclined – per 100 units of the treadmill belt traveled.

## Calories Burned

Walking at a brisk pace can help a 160-pound woman burn about 314 calories per hour. Elevating the treadmill deck to an incline can seriously ramp-up the calories burned. Walking at 3 miles per hour on an incline of 12 percent boosts your heart rate to the same as if you were jogging 6 mph on a flat elevation. Inclined workouts also challenge the leg muscles – the hamstrings, glutes and quadriceps – much more effectively than exercising on a flat deck. For example, a flat incline stimulates about 20 percent of the muscle tissue in your legs, while a 15 percent incline recruits more than 75 percent of the muscle tissue in your legs.

## Indoor vs. Outdoor

While a treadmill simulates walking or jogging outdoors, there is a difference between the two workouts. When you exercise outdoors, you have to battle the wind and varying elevation of the ground. To more accurately simulate the outdoor undulations and wind resistance, set your treadmill deck to a 1 percent grade. A 1996 study published in the "Journal of Sports Sciences" found that the energy expenditure during a five-minute jog was nearly identical between an outdoor run and a jog on the treadmill set at a 1 percent incline.

## Focus on Fat

By adjusting the speed and elevation of the treadmill belt, you can force your body to burn a higher percentage of fat calories. It’s a recipe for melting away body fat. The key is increasing the treadmill deck to the highest percentage you can comfortably do over a 30- to 60-minute workout, and slow down the belt to a 2 mph crawl. This workout plan can help you burn as much as 6.5 fat calories per minute. Comparatively, jogging at 6 mph on a flat treadmill deck burns just 1.9 fat calories per minute. Slow and steady wins the fat battle in this case.