To do the Posterior Plank, sit on the ground with your legs out straight in front of you and your hands down behind your butt on the ground.
Then, driving up through your heels and your hands, press your hips up toward the ceiling and press your chest out. Lean your head back as you bridge up. Squeeze your butt and lift your hips up as high as you can while keeping your legs straight and your chest pressed out. Do not shrug your shoulders at the top as you press your chest out.
Hold at the top of the move with your body in a nice straight line. Make sure to keep your abs tight so you don’t hyperextend your low back. Consciously squeeze your glutes at the top and draw your shoulder blades down and together.
Hold at the top or lower back down and complete reps of the move. If the Posterior Plank is too much, you may want to try the Table Top Bridge.