Know the four rotary centers of the swing
The instructor identifies four rotary centers — the neck, the thoracic spine (the mid-back, the part of the spine between the base of the neck and just above the low back), the shoulders, and the hips. He notes that most of your rotation, including what golfers call 'shoulder turn', actually comes from the thoracic spine rather than the shoulders themselves.
Channel: Mark Immelman
Watch official source at 9:31