The 9.31 Premium Series treadmill from Precor brings the latest design and technical innovations to your home. Whether running or walking, the 9.31 treadmill provides an exceptionally smooth and fluid feel. An innovative design adjusts belt speed to foot speed--fully complementing and supporting your natural stride--while a unique suspension system cushions impact and stabilizes lateral movement, reducing impact on joints, increasing comfort and minimizing fatigue. With a full range of workout programs (8 in total) and advanced options, you'll be able to customize your workout and follow your progress as you achieve your fitness goals. The 9.31 is compatible with heart rate telemetry reading using optional wireless chest strap transmitters.