The horse is allowed to work loose within the area between two gates. As the wheel turns, the gate immediately behind the horse encourages it to move and keep pace with the system. Compared to the other conditioning methods discussed so far, the mechanical exerciser is a major time saver since six yearlings can be exercised at one time. The speed of the exerciser is adjustable, allowing horses to work at speeds ranging from a comfortable walk to a fast trot or canter. They are reversible, allowing horses to be exercised in both directions.
Treadmills provide yet another option for conditioning the sales yearling.
Horses quickly become accustomed to walking, trotting, and cantering on a treadmill. A big advantage of treadmills is the very even and consistent surface that they provide, which is a big plus when trying to minimize lameness problems. Also, because the horse is stationary relative to an observer while moving on the treadmill, this form of exercise allows the trainer to evaluate the horse's style of movement. Since treadmills can be inclined, they provide an opportunity for simulated hill work, an excellent means for developing the back and hindquarters. Incline walking should be introduced very slowly and never exceed 10-15 minutes per session three times per week.