Zusammenfassung

Impaired mobility is a major concern for older adults and has significant consequences. While the widely accepted belief is that improved physical function underlies the effectiveness of targeted exercise training in improving mobility and reducing falls, recent evidence suggests cognitive and neural benefits gained through exercise may also play an important role in promoting mobility. However, the underlying neural mechanisms of this relationship are currently unclear. Thus, our main objective was to investigate whether six months of progressive aerobic exercise training alters frontoparietal network (FPN) connectivity during a motor task among older adults at risk for mobility disability – individuals with mild subcortical ischemic vascular cognitive impairment (SIVCI)—and whether exercise-induced changes in FPN connectivity correlate with concurrent changes in mobility. We focused on the FPN as it is involved in top-down attentional control as well as motor planning and motor execution. Participants were randomized either to usual-care (CON) or thrice-weekly aerobic training (AT). Functional magnetic resonance imaging was acquired at baseline and trial completion. At trial completion, compared with AT, CON showed significantly increased FPN connectivity strength during right finger tapping (p<0.05). Across the participants, reduced FPN connectivity was associated with greater cardiovascular capacity (p=0.05). In the AT group, reduced FPN connectivity was significantly associated with improved mobility performance, as measured by the Timed-Up-and-Go test (r=0.67, p=0.02). These results suggest progressive aerobic training may improve mobility in older adults with SIVCI via maintaining intra-network connectivity of the FPN.