Abstract: A treadmill is disclosed having a belt system carried by a platform structure. The platform structure is pivotally mounted at its rear end to a base structure. The platform is supported at its forward end by a shock absorber/spring system which provides a damped resilient response of the belt and platform when a person's foot lands during running or walking. Carrying the belt system by the platform structure enables the endless belt of the belt system to be maintained closely above the platform even when a runner's foot lands on it with heavy impact. The support of the platform immediately below the belt eliminates lateral slack in the belt which could possibly result in injury to a walker or runner due to an uneven landing surface.