Background: Many studies suggest physical activity reduces risk of dementia and improves global cognitive function in individuals with mild cognitive impairment (MCI). Using commercial wearable technology to measure daily steps is feasible in this population.

Objectives: The purpose of this pilot study was to explore whether 12 weeks of increased physical activity improved cognitive function in individuals with MCI. A wearable activity tracker was used to measure participants' daily steps as a quantifiable measure of daily activity level.

Design: This was a one-group pretest-posttest study.

Setting: Established memory clinic patients within a neurology department in Northern California during 2019.

Participants: 17 enrolled and 14 included for data analysis. There were 7 females and 7 males whose mean age was 76.21 (SD 2.69). 12 participants were White, which reflected the clinic population.

Intervention: Participants were asked to wear an activity tracker for approximately 12 hours a day for 12 weeks and to increase their physical activity as much as possible. They were provided twice a month telephone support.

Measurements: The Montreal Cognitive Assessment (MoCA) was used to measure pretest-posttest cognitive function. Timed Up and Go (TUG) was used to assess fall risk at enrollment. Cumulative step count for the study period was measured with an activity tracker.

Inclusion Criteria:

• Participants had a score of 0.5 on the Clinical Dementia Rating and are on a stable medication regimen for 3 months prior to enrollment.

Exclusion Criteria:

• a diagnosis of dementia; receiving chemotherapy; unstable chronic diseases; surgery with general anesthesia in the prior 3 months; MRI-confirmed brain damage from trauma, stroke, or other neurological disorder; a myocardial infarction < 1 year; a serious or non-healing wound, ulcer, or bone fracture; TUG ≥ 12 seconds; MoCA score >26 or <16; already using a wearable activity tracker; lacked access to the internet; or non-English speaking.