rTMS Combined With Aerobic Exercise for Older Adults With Mild Cognitive Impairment and Comorbid Depression

Mild cognitive impairment (MCI) is a transitional stage between normal aging and dementia and is frequently accompanied by depressive symptoms. Older adults with MCI and comorbid depression are at increased risk of cognitive decline, functional impairment, reduced quality of life, and progression to dementia. Therefore, effective non-pharmacological interventions targeting both cognitive and mental health outcomes are needed.

This study aims to investigate the effects of rTMS alone and rTMS combined with aerobic exercise on cognitive and mental health outcomes in older adults with MCI and comorbid depression. A randomized controlled trial design will be employed. Forty-five eligible participants who provide written informed consent will be randomly assigned to one of three groups: (1) rTMS alone, (2) rTMS combined with stationary cycling exercise, and (3) sham rTMS combined with stationary cycling exercise.

All participants will receive 20 intervention sessions over a 5-week intervention period (4 sessions per week). Intervention sessions will be conducted on Monday, Tuesday, Thursday, and Friday. Participants in the rTMS-alone group will receive a 5-minute rTMS session only. Participants in the rTMS combined with stationary cycling exercise group and the sham rTMS combined with stationary cycling exercise group will receive either active or sham rTMS for 5 minutes, followed by 30 minutes of stationary cycling exercise.

The stimulation target will be the left dorsolateral prefrontal cortex (DLPFC). For sham stimulation, a figure-of-eight coil will be positioned with one wing angled at 90 degrees relative to the scalp and maintained approximately 3 cm from the scalp surface to mimic the sensory experience of active stimulation while minimizing effective cortical stimulation.

Outcome assessments will be conducted at baseline, immediately after completion of the 5-week intervention period, and at a 1-month follow-up. Outcome measures will include cognitive function, depressive symptoms, sleep quality, life satisfaction, self-efficacy, and gait performance. Each assessment session is expected to require approximately 45 minutes.

The findings may provide evidence supporting the application of combined neuromodulation and aerobic exercise interventions for improving cognitive and mental health outcomes in older adults with MCI and comorbid depression.

Inclusion criteria

• Aged 65 to 90 years.
• Diagnosed with mild cognitive impairment (MCI) according to established clinical criteria.
• Presence of depressive symptoms as determined by clinical assessment and Beck Depression Inventory-II (BDI-II).
• Able to communicate and follow study instructions.
• Able to ambulate independently with or without an assistive device.
• Able to provide written informed consent.

Exclusion criteria

• Diagnosis of dementia.
• History of epilepsy or seizure disorder.
• Presence of metallic implants, pacemakers, cochlear implants, or other contraindications to transcranial magnetic stimulation.
• Major neurological disorders, including stroke, Parkinson's disease, traumatic brain injury, or other neurodegenerative diseases.
• Severe psychiatric disorders other than depression.
• Severe cardiovascular, musculoskeletal, or medical conditions that preclude participation in aerobic exercise.
• Severe visual or hearing impairments that interfere with cognitive assessment.
• Current participation in another intervention study.