JMIR Publications

ABSTRACT

Background:

Extensive research suggests that physical activity (PA) is important for brain and cognitive health and may help delay or prevent Alzheimer’s disease and related dementias (ADRD). Most PA interventions designed to help older adults meet PA guidelines to improve brain health have been conducted in laboratory, gym, or group settings that require extensive resources and travel to the study site or group sessions. Novel mobile health (mHealth) interventions focused on PA in free-living environments may offset the burden of ADRD and improve quality of life in aging.

Objective:

This pilot study (Independent Walking for Brain Health NCT03058146) was a 12-week randomized controlled trial (RCT) to investigate the feasibility of providing just in time (JIT) feedback about PA intensity during free living exercise sessions to help older adults meet current PA recommendations (150 minutes per week of moderate intensity PA).

Methods:

Participants were eligible if they were cognitively healthy English speakers between the ages of 65 and 80 without major cardiovascular, neurologic, or mental health conditions who could ambulate independently and undergo magnetic resonance imaging (MRI). Recruitment occurred from 2017 through 2020. Those randomized to the Physical Activity Condition (PAC) received an individualized exercise prescription and an mHealth device that provided heart rate-based JIT feedback on PA intensity, allowing participants to adjust their behavior in real time to maintain MVPA during exercise sessions. Participants assigned to the Healthy Aging Education Condition (HAEC) received a reading prescription consisting of healthy aging topics and completed weekly quizzes about the materials.

Results:

Recruitment for this study began in 2017 and was terminated early in March of 2020 as a result of the COVID-19 pandemic. Forty four participants were randomized to the intervention, with 21 in the PAC and 23 in the HAEC. A follow up manuscript will describe the results of the intervention, discuss screening, recruitment, adverse events, and the participant's opinions about participating in the intervention.

Conclusions:

This small RCT pilot was conducted to determine the feasibility of using JIT heart rate zone feedback to help older adults independently meet PA recommendations while collecting data on plausible mechanisms of change (frontal and medial temporal cerebral blood flow and cardiorespiratory fitness) that may affect cognition (memory and executive function) to help refine a planned Stage II behavioral trial.