Posterior chain pump that decompresses your spine.
Lift with glutes and hams, not a back-arch heave. Don't let momentum fling the legs.
The reverse hyper flips the script: your torso stays fixed on the pad while your legs swing up into hip extension, so the hamstrings get loaded through a big stretched range without a bar compressing your spine. The glutes take over at the top to finish the lift and hold the squeeze. That mix of posterior chain work with zero spinal loading is why it lives in so many squat and deadlift programmes.
On a back extension your legs are fixed and your torso moves. The reverse hyper reverses it, your legs swing while your torso stays supported, which keeps the spine unloaded and lets the hamstrings and glutes do all the moving.
Less than you think. If the pendulum is flinging your legs up and yanking them back down, the momentum is training itself. Use a load you can swing up smoothly and control down every rep.
No. Lift until your legs are roughly in line with your torso and stop there. Heaving into a big arch shifts the stress off the hamstrings and glutes and onto your lower back, which defeats the point.
