Glute Bridge With Squeeze
Then bend your elbows to 90 degrees so that only your upper arms are on the ground and brace your abs. Driving through your heels and upper back and arms, bridge up, lifting your glutes up off the ground.
Squeeze the block and drive your hips up as high as possible without hyperextending your low back. Squeeze your glutes to lift and brace your abs as you extend your hips and squeeze the block. Feel your glutes and even your inner thighs working to help you bridge and hold the block.
Do not worry about exactly how high you bridge up. Just focus on consciously squeezing your glutes at the top and extending your hips. And do not push yourself backward off your heels. You want to also drive up using your upper back too.
Using the block should keep your knees from really caving in or falling open as long as you set up with your ankle, knees and hips in line.
Squeeze your glutes for a second or two at the top and then lower all the way back down to the ground before repeating. Do not lose the block as you bridge and lower. Squeeze and engage the entire time even when you lower to the ground.