Disclosed is a bi-directional resistance exercise machine. The bi-directional resistance exercise machine is comprised of two flywheels that provide constant and variable resistance against the movement of a trolley during a push or pull movement. The bi-directional resistance allows a user to work antagonistic muscles in an efficient manner and in one single machine. Accordingly, the present invention provides resistance against a user while pulling a trolley along a track to work the core, legs, back, and biceps, and resistance against a user while pushing a trolley along a track to work the core, chest, triceps, and shoulders.