Proximity Sensors find a few applications in treadmills for speed and gradient sensing. The speed of the belt is determined by positioning a reed sensor near the pulley driving the belt, and a small flexible magnet either on the belt itself or on the pulley itself. This would mean that the belt tensions should be monitored and kept adjusted so that belt slippage does not lead to wrong speed and distance indications. Apart from speed sensing, the gradient of the treadmill is adjusted by raising the front wheels. Locating reed sensors in a few strategic positions on the arms of the front wheels can also give information to the controller about the angle of the gradient. The continuous information collected by the multiple sensors is then used to save health information to an App on a mobile device or a website.