A hotwalker, within the practice of horse management is a person such as a groom or stable worker who hand walks hot, sweaty horses after a workout, particularly after work on a racetrack. The term hotwalker may also refer to a mechanical device designed for the same purpose.

Hotwalking allows the horse to cool down after hard exercise, which helps the horse's pulse and respiration return to normal, reduces stiffness, and minimizes the risk of health issues such as influenza, or colic.

Mechanical hot walkers cost several thousand dollars, prices varying widely depending on size and construction.

Mechanical hotwalkers come in many designs. The horses on the walker go in a circle, and most hotwalkers can be set to go in either direction.

The most common design in the United States consists of four arms of heavy gauge steel radiating off from a central pivot point containing a motor to move the arms at various speeds, most often set to have horses walk.

More Info: en.wikipedia.org