Assessing Causality of the Association Between Exercise and Neurocognitive Gains

It is well known regular exercise produces both physical and cognitive benefits. Emerging evidence suggests that physical movements or exercise that have concurrent cognitive demands may have more profound effects on cognitive and brain health outcomes. One training program that incorporates these components is the square stepping exercise (SSE). First demonstrated in Japan, this community-based paradigm has already shown to reduce falls risk and presents as a convenient exercise modality for older adults, that can be conducted in a group setting or even the home. The current project aims to examine the efficacy of this SSE community programme in a Singapore context on cognitive and physical health in older adults. This study also aims to quantify the neural correlates underpinning any observed improvements in cognitive and physical function. Specifically, this project will measure indices of neuroplasticity via structural and functional magnetic resonance imaging, transcranial magnetic stimulation, and electroencephalography.

Sample size estimation: n=80 for behavioural primary outcome measures and n=40 subset of larger sample for neuroimaging and neuroplasticity secondary outcome measures [anticipated].

Inclusion criteria

• Older adults aged 55-80
• Sedentary, defined as exercise less than 3 times per week for 30 minutes

Exclusion criteria

• Square stepping exercise:
• Medical conditions preventing them from movement and/or exercise
• Psychiatric conditions
• Cognitive impairment of dementia
• Upper and/or lower limb injuries in the past 6 months
• History of falls in the past 6 months
• Current smokers
• Neuroimaging (all the above in addition to the following)
• Patients who have conductive, ferromagnetic, or magnet-sensitive metals implanted in head (e.g., aneurysm clip, stent).
• Implanted medical device: e.g., cardiac implants, cochlear implant, aneurysm clips, cardiac pacemaker etc.
• Non-removable metal braces or retainer (dental fillings ok).
• Permanent tattoos on head.
• Deep brain stimulators.
• Previous brain surgery or injury.
• Patient with epilepsy or any other seizure history, or immediate family history of epilepsy.
• Clinical EEG that was abnormal or where seizure activity had not been ruled out.
• Patients with history of head injury with loss of consciousness are to be investigated about the history if/before being recruited.
• Diagnosis or possibility of neurological disorder (including stroke).
• Psychiatric condition.
• Major or unstable medical condition/surgery.
• Current or suspected pregnancy or lactation.
• Illicit drug use in the last 7 days.
• Alcohol use in the last 12 hours or more than 3 standard drinks in last 24 hours.
• Recent insomnia or severe sleep deprivation.
• Participation in another study involving brain stimulation (e.g., TMS, TDCS) in the past 7 days.