The Jacobs ladder is an unusual treadmill in that its actually a climbing treadmill. Climbing ladders works out your upper body as well as your legs to give a total cardio workout. Its been designed so that the faster you go, the faster it goes. If you try to climb towards the top it goes faster and if you climb at the bottom it goes slower. If you stop all together it will slowly drop you to the bottom.
There is also a computer that monitors speed, calories, distance, time and heart rate which is all displayed on a console.