Older adults traditionally adapt their discrete aiming movements, thereby traveling a larger proportion of the movement under closed-loop control. As the beneficial impact of a physically active lifestyle in older age has been described for several aspects of motor control, we compared the aiming performance of young controls to active and sedentary older adults. To additionally determine the contribution of visual feedback, aiming movements were executed with and without saccades. Results showed only sedentary older adults adopted the typical movement changes, highlighting the impact of a physically active lifestyle on manual aiming in older age. In an attempt to reveal the mechanism underlying the movement changes, evidence for an age-related decline in force control was found, which in turn resulted in an adapted aiming strategy. Finally, prohibiting saccades did not affect older adults’ performance to a greater extent, suggesting they do not rely more on visual feedback than young controls.
Van Halewyck, Lavrysen, Levin, and Helsen are with the Department of Kinesiology, Movement Control and Neuroplasticity Research Group, KU Leuven, Belgium. Elliott is with the Research Institute for Sport and Exercise Sciences, Liverpool John Moores University, UK. Address author correspondence to Werner F. Helsen at firstname.lastname@example.org.