The relationship between objective physical activity and change in cognitive function
Alzheimer's and Dementia
School of Medical and Health Sciences
Alzheimer's Association / Alzheimer's Drug Discovery Foundation / Science and Industry Endowment Fund / Dementia Collaborative Research Centres / Victorian Government's Operational Infrastructure Support program / Australian Alzheimer's Research Foundation / National Health and Medical Research Council / The Yulgilbar Foundation / Research Training Program (RTP) scholarship
NHMRC Number : GNT1197315
Introduction: The current study investigated the association between objectively measured physical activity and cognition in older adults over approximately 8 years. Methods: We utilized data from 199 cognitively unimpaired individuals from the Australian Imaging, Biomarkers and Lifestyle (AIBL) study, aged ≥ 60. Actigraphy was used to measure physical activity (intensity, total activity, and energy expenditure) at baseline. Cognition was assessed using a comprehensive cognitive battery every 18-months. Results: Higher baseline energy expenditure predicted better episodic recall memory and global cognition over the follow-up period (p = 0.031; p = 0.047, respectively). Those with higher physical activity intensity and greater total activity also had better global cognition over time (both p = 0.005). Finally, higher total physical activity predicted improved episodic recall memory over time (p = 0.022). Discussion: These results suggest that physical activity can preserve cognition and that activity intensity may play an important role in this association. Highlights: Greater total physical activity predicts preserved episodic memory and global cognition. Moderate intensity physical activity ( > 3.7 metabolic equivalents of task [MET]) predicts preserved global cognition. Expending > 373 kilocalories per day may benefit episodic memory and global cognition.