ActivityAware: Wearable System for Real-Time Physical Activity Monitoring among the Elderly

George Boateng, M.S., reports on new Amulet research in his Master’s thesis, available as a Dartmouth Computer Science Technical Report.

Abstract. Physical activity helps reduce the risk of cardiovascular disease, hypertension and obesity. The ability to monitor a person’s daily activity level can inform self-management of physical activity and related interventions. For older adults with obesity, the importance of regular, physical activity is critical to reduce the risk of long-term disability. In this work, we present ActivityAware, an application on the Amulet wrist-worn device that monitors the daily activity levels (low, moderate and vigorous) of older adults in real-time. The app continuously collects acceleration data on the Amulet, classifies the current activity level, updates the day’s accumulated time spent at that activity level, displays the results on the screen and logs summary data for later analysis.

The app implements an activity-level detection model we developed using a Linear Support Vector Machine (SVM). We trained our model using data from a user study, where subjects performed common physical activities (sit, stand, lay down, walk and run). We obtained accuracies up to 99.2% and 98.5% with 10-fold cross validation and leave-one-subject-out (LOSO) cross-validation respectively. We ran a week-long field study to evaluate the utility, usability and battery life of the ActivityAware system where 5 older adults wore the Amulet as it monitored their activity level. The utility evaluation showed that the app was somewhat useful in achieving the daily physical activity goal. The usability feedback showed that the ActivityAware system has the potential to be used by people for monitoring their activity levels. Our energy-efficiency evaluation revealed a battery life of at least 1 week before needing to recharge. The results are promising, indicating that the app may be used for activity-level monitoring by individuals or researchers for epidemiological studies, and eventually for the development of interventions that could improve the health of older adults.

Advisors: David Kotz, Ryan Halter, John Batsis

New grant to apply Amulet to study obesity in elderly people

Dr. John Batsis, DHMCThe Amulet team is collaborating with geriatrician Dr. John Batsis of Dartmouth-Hitchcock Medical Center to explore the use of the Amulet in developing intervension methods to help obese elderly people maintain function while they remain living at home.  This “grant … from the National Institute on Aging will allow Dr. John A. Batsis to focus on strategies for improving health care delivery and wellness in older adults with obesity by using video conferencing, personal monitoring devices and frequent coaching by healthcare providers.” [press release]

Check out the video interview with Dr. Batsis on WCAX television.

This research is supported by the National Institute On Aging of the National Institutes of Health under Award Number K23AG051681.