Tip: Modified Reverse Hyper

You should feel this variation almost entirely in your glutes. Start with body weight for around 10 reps.

With a regular reverse hyper, it's easy to descend too far down and go into lumbar flexion at the bottom, which puts tremendous shear on the lumbar spine. Likewise, it's easy to come up too high and hyperextend your lumbar spine at the top, which is also problematic, especially under heavy loads. To avoid this issue, try moving the legs "in and out" instead of "up and down."

Lie prone on a table or bench with your legs hanging off the edge, your knees bent and your hips flexed to approximately 90 degrees. From there, brace your core, squeeze your glutes, and extend your legs straight back behind you. Hold for a brief pause and return to the starting point. When your legs are fully extended, there should be a straight line going from your feet to your head. Since your legs aren't moving up and down in the vertical plane, it's much easier to keep a neutral spine, thereby allowing you to hone in on the glutes without irritating your lower back.

Start with just your own bodyweight until you get the hang of it. Trust me, it's harder than you might think. You should feel it almost entirely in your glutes. If you feel it in your lower back, you're probably raising your feet up too high.

Now Add Weight

Once you can comfortably do a few sets of 8-10 reps with just bodyweight, you can progress by adding ankle weights or putting a small dumbbell between your feet. If you're doing them correctly with controlled form, it won't take much weight at all (around 10-25 pounds tops).

You can also modulate the difficulty with your setup position – the more of your torso that's resting on the bench, the easier it will be, and vice versa.