Interplay of physical and cognitive performance using hierarchical continuous-time dynamic modelling and a dual-task training regime in AD patients

Various longitudinal studies report positive effects of physical exercise on cognitive performance in patients with Alzheimer's disease (AD). However, most of these studies fail to capture the dynamic nature of the change and interplay of physical fitness and cognition. To overcome this limitation, we employ a hierarchical continuous-time dynamic model to analyze data of a 24-week physical and cognitive dual-task training regime (3 sessions per week) in older adults with AD (N = 17). The model was specified with two fully connected state variables enabling bidirectional effects between physical and cognitive performance over measurement occasions. The results show that physical performance is dynamically linked to cognitive performance. In line with earlier findings, higher physical performance predicted improved memory recognition performance in terms of faster reaction times.