The reverse spine angle swing flaw is evident when the player demonstrates a lean of their upper body toward the target. For a right handed golfer this would be to their left at the top of their backswing.
THIS LEAN OF THE UPPER BODY TOWARD THE TARGET IS A KEY CHARACTERISTIC OF THE REVERSE SPINE ANGLE.
This position makes it very difficult to properly sequence your downswing. The proper kinematic sequence is for the hips and pelvis to begin the movement of the downswing followed by the upper body, arms, and finally the hands and club. This allows for the energy stored in the muscles of the trunk to be released in such a way that maximizes power into the ball. If this sequence is abnormal then power is bled from the swing and increased forces can be put into the body. This position also makes it difficult to find the proper path of the golf club as it travels toward the ball, which leads to inconsistency in the path of your ball toward your selected target.
In order to maintain your spine angle during the backswing your body has to be able to do certain things. First, you have to be able to separate your upper body from your lower body. If you are unable to do this it could be because of a mobility issue ( joint stiffness, or muscular tightness). Another reason why you may not be able to separate your upper body from your lower is because of what is called a motor control/stability issue. This is when your body must be trained in how to properly move.
Mobility in the thoracic spine (upper part of your back) as well as your hips are critical during your backswing. If mobility in these areas is limited your body will lean and sway to compensate. This compensation is the reverse spine angle swing flaw. This position puts a lot of stress on the right side of your low back.
Stability in the core and around the hips is critical to efficiently move and properly sequence your swing. We know stability is an issue when we test you using the TPI screen and other exam techniques. Working on strengthening the core and looking at your rolling patterns is a way that we help to train your stability.
Try this exercise to ensure you are keeping your pelvis in neutral. This is another body issue that can cause you to extend or arch your back which then puts you in a reverse spine angle position.