The ProForm Trainer 420's six programmed workouts allow you to reach your fitness goals in the least possible time. The music port is compatible with almost all MP3 players so you can plug in your iPod and work out to your favorite music. Each of the six built-in workouts is designed by a Certified Personal Trainer so you can quickly reach your fitness goals. The Trainer 420 Treadmill also features a powerful 1.5 chp motor, a contact heart rate monitor, and a workout fan. The cushioned tread belt can reduce the impact on your joints by 15% compared running on hard surfaces.