Comparisons of hip-worn and ankle-worn accelerometers on measuring physical activity and their correlations with perceived activity level in community-dwelling older adults.

backgroundAging leads to declines in muscle strength, balance, and cardiopulmonary function, reducing mobility and increasing health risks. Accurate monitoring of physical activity is essential to understand its impact on health outcomes in older adults. This study aimed to evaluate the effectiveness of hip-worn and ankle-worn accelerometers in capturing physical activities in older adults, comparing their performance to self-reported activity across weekdays and weekends.

methodsForty healthy participants aged 51-82 years completed the International Physical Activity Questionnaire (IPAQ) and wore an ActiGraph GT3X+ accelerometer on both their right hip and ankle for four consecutive days, covering two weekdays and two weekends. Data from the accelerometers were analyzed to compare step counts and the ability to detect sedentary, light, moderate, and vigorous activities between the two sensor placements.

resultsThe ankle-worn accelerometer recorded higher step counts and more light physical activities. In contrast, the hip-worn accelerometer detected more moderate to vigorous physical activities. Self-reported physical activity was well correlated with step counts and sedentary/light activities on weekdays, but failed to reflect moderate to vigorous activity and all activities on weekends. SIGNIFICANCE: Ankle-worn accelerometers are more effective in estimating light activities, which dominate the daily activity patterns of older adults. Hip-worn accelerometers better capture intensive activities. Self-reports demonstrated limited reliability in assessing physical activity on weekends. These findings enhance the understanding of physical activity patterns in older adults and inform interventions aimed at promoting healthy aging, especially regarding activity monitoring and the choice of accelerometer placement.