White matter hyperintensities and lower extremity physical function before and after an aerobic exercise intervention in healthy older adults

Background: Age-related declines take many forms including white matter deterioration, cognitive impairments, and mobility limitations, all of which can have practical implications, such as falling and making risky pedestrian decisions. Modifiable lifestyle interventions, like physical activity, provide ways to mitigate or ameliorate the range of age-related declines. This dissertation examined the relationships between lower extremity physical function and a representative measure of age-related cerebral small vessel disease, white matter hyperintensity (WMH) volume in the brain, before and after an aerobic exercise intervention in a sample of relatively young and healthy older adults. Analyses also examined the role of WMH volume, physical function, and cognition on virtual reality street crossing risk assessment. Methods: Data were analyzed from 177 older adults (M age = 65) who completed the Fit and Active Senior Trial (FAST), a six-month physical activity intervention including three groups: stretching, strengthening, and stability (SSS); dance (Dance); aerobic walking (Walk). Results: The baseline relationship between greater WMH volume and worse lower extremity physical function was weak in this sample and, unsurprisingly, WMH volume did not change over the six-month intervention. Regardless of intervention group, greater standardized improvement in lower extremity physical function was significantly predicted by lower baseline WMH volume, greater baseline gait self-efficacy, and better baseline fitness, uniquely and in interaction. In a separate model, greater improvements in lower extremity physical function were observed in adults assigned to the Dance condition who had greater improvement in gait self-efficacy and/or lower initial WMH volume. Conclusions: The results reported here suggest that in sedentary older adults, the transition to physically active can benefit lower extremity physical function regardless of the type of activity. However, these gains seem to be greatest over the six-month period in individuals who at baseline have lower WMH volume, better gait self-efficacy, and better fitness.

Name thesis:degree_name

Ph.D.

Level thesis:degree_level

Dissertation

Discipline thesis:degree_discipline

Psychology

Grantor

University of Illinois at Urbana-Champaign

Year dc:date

2017

Author dc:creator

• Banducci, Sarah E

Contributors dc:contributor

• Kramer, Arthur
• McAuley, Edward
• Morrow, Daniel
• Hillman, Charles
• Dolcos, Florin

• Aging brain
• Cognition
• Physical activity
• Physical function
• Mobility
• Pedestrian safety

Statement dc:rights

• Copyright 2017 Sarah Banducci

Language dc:language

en

Handle dc:identifier

http://hdl.handle.net/2142/97574

OAI identifier oai:identifier

oai:www.ideals.illinois.edu:2142/97574