While core strength can help that is typically not the source of the problem with over rotation in the hop. How is your posture in the last 2-3 steps of the approach? Do you lunge in to the takeoff head first? Are you pushing with your feet behind you in the last couple steps or are you pushing upwards? How is your arm swing at the hope takeoff? Answering these questions will help to diagnose the source of your problem.
ELITETRACK Founder