“Core Stability” has become a very popular term when discussing topics ranging from functional performance in athletes to rehabilitation for patients with low back pain. The exercise ball has long been used to promote core stability through specific exercises aimed at activating core muscles including the abdominals, low back, and pelvic stabilizers. The use of unstable surfaces such as a Thera-Band® exercise ball has been shown to increase muscle activity compared to a stable surface by providing additional challenge to postural stability. Researchers have shown, however, that exercises on an unstable surface reduce force output, suggesting that traditional resistance training exercises should not be performed on an unstable surface when the goal is to increase core activation. This lack of force output on unstable surfaces is thought to be related to a lack of core stability.

Researchers in New Zealand set out to determine if the loss in force output while performing an overhead press exercise on an exercise ball was related to core muscle endurance. They were interested in the ‘specificity vs. generality” of core stability; in other words, is core stability related to overall physical performance, or simply a measure of core muscle endurance?

30 resistance-trained, healthy young males participated in the study. More >