Cody Bellinger shows us how he activates his back hip with the "Step Back" drill. Notice the timing of the move. When doing this drill, make sure the heel of the foot is engaging the ground so that the back hip/glute gets activated.
In this video, Mookie Betts is showing us how to create and maintain space throughout his move to the ball. This drill is designed to assist a hitter to engage his core as his power source instead of the big muscles in the arms/back.