40 patients with chronic low back pain were randomized to undergo an 8-week exercise program involving a hook-lying position - drawing in of the abdominal wall - with or without active ankle dorsiflexion. The purpose of this study was to determine whether the addition of ankle dorsiflexion has a significant effect on physical function, pain and core stability in these patients. Results indicated that, although both the experimental and control interventions yielded significant improvements in physical function, pain and core stability over time, these improvements were significantly greater in the experimental group compared to the control group.