A treadmill including a frame, a power supply, and a motor coupled to the frame and to the power supply. The motor includes a shaft and a stator fixedly coupled to the frame, at least one bearing coupled to the shaft, and a rotor coupled to the at least one bearing. The rotor includes at least a portion that surrounds at least a portion of the stator. The treadmill further includes a walking-belt assembly coupled to the frame and to the rotor.