The reverse hyper machine will strengthen the posterior chain and decompresses the spine. You can use it with a strap or roller. If using a strap, just put the strap around your ankles. Position yourself so that your lower half is hanging off the pad and grab the handles.
At the top, contract hard; at the bottom of the movement relax. Control the pendulum. Don't let it swing too aggressively.
Do these twice a week. Here's an example of how to program it: