Stability of the spine is necessary for preventing pain and enhancing performance ( Liebenson, 2006 Liebenson C. Rehabilitation of the Spine: a Practitioner's Manual. second ed. Lippincott/Williams & Wilkins, 2006 Google Scholar , McGill, 2006 McGill S.M. Ultimate Back Fitness and Performance. second ed. Wabunu, 2006 Google Scholar ). Core muscle endurance is a key quality to train. Many exercises have been developed for the core including traditional ones such as sit-ups which have been recently called into question ( McGill, 2006 McGill S.M. Ultimate Back Fitness and Performance. second ed. Wabunu, 2006 Google Scholar ). Training the spine in a neutral posture which reinforces the natural upright curve of the low back has been recommended as a form of functional training ( McGill, 2006 McGill S.M. Ultimate Back Fitness and Performance. second ed. Wabunu, 2006 Google Scholar ).