Disclosed is a golf exercise weight machine for anaerobically strengthening the large rotary muscles of the body--including the upper thigh, trunk and abdomen, and shoulders--most used in performing a golf swing. Preferably, the device includes a floor mounted base to which a yoke is rotatably attached to fit around the shoulders and arms of a user, so that during operation the user's body remains oriented in the proper swing position so as to mimic and improve the golf swing by strengthening the appropriate muscles. A weight stack provides variable resistance during the simulated golf swing, and the device offers adjustment over multiple degrees of freedom and it can accommodate both right-and left-handed swings.