Purdue University, West Lafayette, IN
Our office will remain closed through Friday, September 18th as we continue to assess the damages caused by Hurricane Sally. ActiGraph team members are working remotely, however shipping delays should be expected at this time. We expect to resume regular business hours on Monday, September 21st. If you need immediate assistance, please contact us by email at firstname.lastname@example.org and we will respond as quickly as possible. Thank you for your continued support.
Spatial Clustering of Objectively Measured Physical Activity in Massachusetts Adults: Preliminary Findings
- Presented on May 28, 2014
Background: Accelerometers and global positioning system (GPS) units to monitor participants’ activity allow for a dynamic spatial examination of the locations where physical activity occurs. The application of spatial clustering analysis to these geographically linked physical activity data may provide a better understanding of how moderate-to-vigorous physical activity (MVPA) concentrates in certain locations among individuals and eventually may provide insights into important environmental determinants.
Purpose: To detect and describe patterns of spatial clusters of objectively measured MVPA in a sample of Massachusetts adults.
Methods: This study involved spatial analysis of minute-by-minute physical activity data obtained via accelerometry and linked to geographic coordinates via GPS monitoring. The data were collected from 144 Massachusetts adults (age = 44±13 yrs) recruited at ﬁve trails in Massachusetts. Participants wore an ActiGraph accelerometer and small GPS unit for four days in 2004-2005. Minutes with an activity count ≥ 760 were classiﬁed as MVPA. A spatial scan statistic was used to detect statistically signiﬁcant (p <.05) spatial clusters of high rates of MVPA. A relative risk (RR) is generated for each cluster, which indicates that minutes inside the cluster have high rates of MVPA relative to minutes outside the cluster.
Results: Out of a total of 61,600 monitoring minutes with geographic coordinates, 24,866 were classiﬁ ed as MVPA (40%) and 36,734 were inactive or light intensity. Seventy-ﬁ ve spatial clusters of MVPA were identiﬁ ed with RRs ranging from 1.34 to 2.48. Fifty-six percent of MVPA minutes were inside clusters (n = 13,982). The number of participants in clusters ranged from 1-37. The mean distances from participants’ homes to the cluster centroids ranged from 0.33 to 50.3 km; and the cluster radii were all less than 5 km. Twenty-eight clusters (37%) were located inside the city of Boston, 25 (33%) intersected the ﬁve study trails, and 30 (40%) occurred near participants’ homes.
Conclusions: Spatial cluster methods detected areas with a greater concentration of objectively measured MVPA. As expected, some clusters were located on study trails. However, a substantial number of clusters were found off trails and near participants’ homes
- Kosuke Tamura 1
- Robin C. Puett 2
- David B. Klenosky 1
- William A. Harper 1
- Hao Zhang 1
- Philip J. Troped 3
University of Maryland, College Park, MD
University of Massachusetts, Boston, MA
ACSM 2014 Annual Meeting