Back stability and Hamstring integration
+ Shoulder Blades are connected to the ground, Spine is straight and Neutral (means there is a slight curve in the low back, not low back jammed into the ground or hyper lifted)
+ Lift butt and back into the air, hold, and bend to knees to 90 degrees with out flopping all over the place, sounds easier than it is.
+ Pace is still deliberate but faster, no snapping, keep control until the burn behind your legs is too much. stop and relax with legs straight on the ball
+ Keep the breath moving, do not hold throughout the exercise.
2-3 sets of 10-20 reps good leg day addition