A vibration apparatus and also a motor assembly are provided to enhance vibrational massage therapy and to improve non-impact exercise. In particular, the motor assembly generates vibrations of differing amplitudes utilizing a single motor to drive a shaft that, in turn, rotates an eccentric weight whose rotational axis is non-coaxial with the shaft's rotational axis. The reversal of the direction in which the motor rotates the shaft changes the amplitude of the resulting vibrations communicated to a platform. Thus, vibrational amplitude most suitable for a particular application or purpose may be selected.