Adaptations in pelvis trunk coupling variability in response to fatiguing exercise

The purpose of this study was to determine if coordination variability between the trunk and pelvis during walking turns is reduced in response to fatiguing muscle exercise. The secondary purpose was to compare two statistical methods of quantifying variability; Vector Coding and the Ellipse Area Method. Twelve healthy adults performed multiple walking turns before and after fatiguing paraspinal exercise. Axial plane coordination between the trunk and pelvis and the coordination variability across trials were calculated. Coordination variability decreased post-exercise in most participants, most significantly when quantified with Vector Coding. Results from Vector Coding and the Ellipse Area Method were highly correlated. This research indicates that the magnitude of coordination variability, and therefore available degrees of freedom, is influenced by fatiguing muscle exercise.