Sex Differences in the Relationship Between Physical Activity and Cognitive Health in Ethnically Diverse Older Adults

The global population is aging rapidly, accompanied by a rise in dementia cases, particularly among females and ethnic minority groups. Physical activity (PA) may mitigate the effects of aging on brain health and promote cognition in older adults, with benefits varying by biological sex and ethnicity. Data from the Health and Aging Brain Study – Health Disparities, a community-based cohort of 3585 Hispanic, Non-Hispanic Black (NBH), and Non-Hispanic White (NHW) older adults, were used. The Rapid Assessment of PA questionnaire categorized participants into no/little and high PA groups. Cognitive composites were created for global cognition, executive functions, and episodic memory. Plasma biomarkers of neurodegeneration were obtained: amyloid-beta (Aβ)40, Aβ42, neurofilament light, total tau, and pTau-181. Hippocampal and subregion volumes and dorsolateral prefrontal cortex thickness were measured. Analysis of covariance was performed to examine the interaction between PA group, sex, and ethnicity for each outcome, adjusting for age, education, APOE4, cardiovascular risk, smoking, and alcohol use, with additional adjustments for Mini-Mental State Examination score, intracranial volume, scanner type, and number of slices segmented, where applicable. Compared to no/little PA, high PA was associated with higher global cognition and executive functions in Hispanic, NHB, and NHW females and Hispanic males (p’s≤0.01; 3-way interaction p’s<0.063). High PA females showed lower levels of Aβ40 and total tau compared to no/little PA females (p’s≤0.03; 2-way interaction p’s<0.068). Compared to their no/little PA counterparts, high PA NHW males showed larger right subiculum volumes (p≤0.01; 3-way interaction p<0.099), while high PA females had greater right CA1 and dentate gyrus volumes (p’s≤0.03; 2-way interactions p’s<0.099). PA is beneficial for cognition in older age in a sex- and ethnicity-dependent manner. Overall, high PA was associated with higher global cognition and executive functions in females and Hispanic males, lower Aβ40 and total tau load in females, and greater right subiculum and CA1 volumes in NHW males and females, respectively. Thus, PA holds promise as a modifiable factor for healthy brain aging, and there is a need to consider sex and ethnicity in the development of personalized PA interventions.

Name thesis:degree_name

Master of Science (MSc)

Discipline thesis:degree_discipline

Kinesiology

Grantor dc:publisher.institution

Graduate Studies

Year dc:date.issued

2025

Author dc:creator

• Nel, Jansie H.

Advisor dc:contributor.advisor

• Barha, Cindy K.

Committee members dc:contributor.committeemember

• Bodnar, Tamara S.
• McDonough, Meghan H.
• Goodarzi, Zahra

• cognitive aging
• physical activity
• sex differences
• ethnicity
• biomarkers of neurodegeneration
• neuroimaging
• post-menopause

Statement dc:rights

• University of Calgary graduate students retain copyright ownership and moral rights for their thesis. You may use this material in any way that is permitted by the Copyright Act or through licensing that has been assigned to the document. For uses that are not allowable under copyright legislation or licensing, you are required to seek permission.

Language dc:language.iso

en

DOI

https://dx.doi.org/10.11575/PRISM/50595

OAI identifier oai:identifier

oai:ucalgary.scholaris.ca:1880/123001