An exercise device is provided together with a method for using the device which, when used either independently or in combination with a conventional exercise apparatus, generates a series of pulse forces in the same direction as the resistance force applied by the conventional apparatus in combination with which the present device is utilized, and in a direction opposite to that applied by the subject utilizing the exercise device, and with force sufficient to move the body member of the subject a short distance and thereby to stretch the muscles of the body member with each pulse force. The stretching of the muscles by the application of the pulse forces results over a period of time in the strengthening of the body member muscles to a greater degree than would occur as a result of exercising with the conventional apparatus alone.