A treadmill is an exercise machine used for walking or running while staying in the same place. It has a moving platform over a conveyor belt driven by an electric motor. The belt moves towards the rear which forces the user to move forward just as we walk or run. There’s a heart rate counter over the treadmill screen. It also allows you to control the belt’s speed. Besides the electric ones, there are manual treadmills which require the user to push the belt with their feet in order to move it.