Underwater treadmill is a treadmill which is submerged in water and provides exercise to people who have undergone total hip replacement. Underwater treadmill is a key component in rehabilitation centers to increase muscle strength and motion of hip. It is also used in Veterinaries to improve the motion of animals like dogs, horses, etc, increase their resistance and make their movements more swift and smooth.

Underwater treadmill consists of a treadmill submerged in water pool. The water pool in an underwater treadmill is normally maintained at chest height of the person to whom exercise is advised by doctors or recommended by medical specialists. The person then walks or runs at any desire pace on the underwater treadmill. An underwater treadmill has a conveyor belt on which the person walks or runs. The walking belt of the underwater treadmill reacts to the input it receives from the user