Biomarker and cognitive improvements after a single bout of interactive Cognitive and Physical Exercise (iPACES v2.75): Results of a multi-site pilot study

Objective: Researchers are focusing on behavioral interventions to counteract the cognitive decline associated with dementia. The interactive and Physical Cognitive Exercise System (iPACES v2.75) study at Union College is a single-bout multimodal intervention, consisting of pedaling an under-desk elliptical which controls progress while playing a video game, for patients with mild cognitive impairment (MCI). Our investigation focuses on the neurobiological mechanisms of cognitive decline by looking at the correlation between changes in biological markers and improvements in cognitive function. Participants and Methods: 27 older adults were recruited from multiple sites in NY and MA. Participants pedaled an under desk elliptical and used an iPad for iPACES, in which they traveled along a virtual bike path and completing errands. Two domains of cognitive function: executive function and verbal memory, were measured pre and post exercise with the paper and electronic Stroop (A:C ratio and CCII metric of BrainBaseline) and ADAS-COG. Salivary samples to analyze biomarker changes were taken before and after the exercise. The samples were assayed using the Enzyme-Linked Immunosorbent Assay (ELISA) for IGF-1, alpha-amylase, and cortisol. Paired t-tests were used to evaluate pre to post changes in IGF-1, Alpha-Amylase, cortisol, Stroop, and ADAS-Cog. Results: Significant improvements in the overall sample were noted on the ADAS-Cog (p = .05), Stroop CCII (p = .01) and alpha amylase (p = .01). There was a significantly greater improvement among MCI on the Stroop CCII (p = .04) and alpha amylase (p = .04). Conclusions: Our results support the idea that alpha-amylase is an effective biomarker for multi-modal interventions for patients with MCI. Since there was a significant improvement in the increase in alpha-amylase, it shows that there was an effective physiological response to the physical exercise that could be part of the broader neurobiological mechanisms leading to cognitive improvements. Further investigation is needed into single-bout interventions to understand how to maximize the effectiveness of the exercise to spur the neurobiological mechanism. Our study supports the notion that the combined physical and mental exercise benefits cognition, and should be the basis of more interventions and research for patients at risk for dementia. Authors: Kartik Nath, Professor Cay Anderson-Hanley