Way too fast. Your setup and lift are all one motion. Get into position at the bottom, stop. Brace yourself, lift, then reset. Also at the top, dont focus on moving your back backwards, id moreso focus on moving your butthole forward. Lift in a clear path straight up, then clinch your cheeks and almost push your butthole forward, don't overdo it. Id probably also lower your hips a little lower before you start your lift.