As most golfers know, setup at address is critical to hitting the ball well. Along with grip and stance, spinal posture is right at the top of the the list of things to consider when you set up over the ball. Proper spinal posture allows a golfer to maximize rotational power of the trunk while minimizing injury risk.
Ideally a golfer will display neutral spine posture at address, meaning that the back is generally flat. This places the facet joints of the spine in a position so that they can move and rotate without too much stress. It also places the muscles on enough slack to allow for proper trunk rotation during the swing. Neutral spine allows a golfer to maximize their trunk rotation, which usually means more power, while reducing the chance of injury.
In C-posture a golfer displays excessive rounding of the upper back at address. This limits the golfer’s ability to rotate due to the position of the joints in the upper back and also due to the tension created in the muscles of the upper back. Limited rotation usually leads to decreased ability to rotate and generate power. Often times golfers will compensate for this lack of rotation in the upper back by using faulty mechanics that place the lower back, neck, and shoulder at risk for injury.
In S-posture a golfer displays increased arching of the lower back. Much like C-posture, the end result of this is that the golfer will experience decreased rotational range of motion. But how it happens is different. In S-posture the arching of the lower back leads to compression of the facets joints. In addition to decreased rotational range of motion, this leads to increased risk of injury to the facet joints of the lower back.
As simple as this may seem, many golfers have a very hard time achieving neutral spine posture at address. Some golfers just need to practice in front of a mirror more, while others have physical limitations that prevent them from getting into neutral when they setup. If you’re having a hard time finding neutral, consider consulting your local TPI certified golf or medical professional.