The Effect of Exercise on Cognition in Older Adults At-risk for Diabetes: A Feasibility Pilot Study

The Effect of Resistance Training on Cognitive Function and Brain Health in Older Adults At-risk for Diabetes: A Feasibility Pilot Study

Older adults with type 2 diabetes experience cognitive decline and are at higher risk for developing dementia. Consequently, older adults at-risk for developing type 2 diabetes (based on body mass, glucose levels) are at higher risk for cognitive decline, and intervening at this point may prevent or delay the onset of such decline. One promising lifestyle intervention that has been shown to improve cognitive function in other populations is exercise. However, before investigators can examine whether exercise will improve cognitive function and brain health (structure and function) in this at-risk population, a feasibility pilot study is needed to determine whether a larger-scale trial would be viable.

Investigators will conduct a six-month randomized control trial (RCT) exercise intervention. Thirty older adults (aged 60-80) at-risk for diabetes will be randomly assigned into one of two groups: 1) Resistance training, or 2) Balance and Tone training (control). All participants will engage in three one-hour exercise classes per week. Once a month, a neutral assessor will visit the classes to evaluate the quality of the classes for participants. Assessments will be made at baseline, midpoint (three months) and trial completion (six months), and will include cognitive testing, health questionnaires, physical testing, and magnetic resonance imaging (MRI; to assess structural and functional brain changes). Throughout the study, investigators will examine data for trends in successful recruitment strategies and rates of recruitment and adherence to inform future clinical trials in this population. Research assistants (n = 30) in the study will complete an anonymous feedback survey upon completion of their volunteer term, to assist in improving the study for future participants and volunteers.

Inclusion Criteria:

1) be community-dwelling 2) be aged 60-80 years 3) be "at-risk" for diabetes, where they have one of the following: i) blood glucose level of 6.1-7 mmol/L, ii) BMI > 25, or iii) score > 21 on the CANRISK diabetes questionnaire 4) score > 24/30 on MMSE 5) score > 6/8 on Lawton and Brody's Independent Activities of Daily Living (IADL) scale 6) have visual acuity of at least 20/40, with or without corrective lenses 7) speak and understand English fluently 8) complete the Physical Activity Readiness Questionnaire (PAR-Q) 9) obtain physician's clearance to start a supervised exercise program

Exclusion Criteria:

1) have a current medical condition for which exercise is contraindicated 2) have participated regularly in resistance or aerobic training in the last 6 months 3) have been diagnosed with neurodegenerative disease (including dementia, Alzheimer's disease, or Parkinson's disease) 4) have experienced a vascular incident (e.g., stroke, myocardial infarction) 5) have been diagnosed with a psychiatric condition 6) have untreated depression 7) are currently on hormone replacement therapy 8) have clinically significant peripheral neuropathy or severe musculoskeletal or joint disease 9) are currently taking psychotropic medications 10) are unable to participate in MRI (have metal or electronic implants, or are claustrophobic)