THE SCHOOL OF CITY AND REGIONAL PLANNING
GEORGIA INSTITUTE OF TECHNOLOGY
Under the provisions of the regulations for the degree
DOCTOR OF PHILOSOPHY
on Wednesday, December 12, 2018
11:45 AM – 1:45 PM (Eastern Time)
in Architecture West Room 250
will be held the
“Red Hot American Summer: Extreme Heat and Physical Activity of Adults”
The Examiners Are:
Dr. Brian Stone (Chair)
Dr. Felipe Lobelo
Dr. Michael Elliott
Dr. Michelle Kegler
Dr. Godfried Augenbroe
Dr. Regine Haardoerfer
Faculty and students are invited to attend this examination.
With only one in five adults reaching the levels of physical activity recommended by the 2008 Physical Activity Guidelines for Americans, public health practitioners and city planners are making concerted efforts to promote activity through formal interventions and the design of spaces, respectively. To inform physical activity interventions, researchers examine which factors associate with physical activity, one of which is temperature. The majority of studies exhibit a significant positive association between temperature and physical activity, yet no studies examine exceptionally hot summer days, which disproportionately impact cities and are set to become more prevalent in the future. This dissertation tests three novel questions: 1) how do hot days associate with outdoor, indoor, and total physical activity; 2) how do hot days influence the effect of built environment factors on outdoor physical activity; and 3) how do heat waves – consecutive hot days – associate with outdoor, indoor, and total physical activity?
This work made use of self-reported physical activity and demographic data collected during summer 2016 for a National Science Foundation project (NSF award number: 1520803). The study sample included a spatial and demographic mix of ~50 adults per study city (i.e., Atlanta, Detroit, and Phoenix). Heat was measured as both hot days and heat waves, utilizing air temperature and relative humidity data collected at each city’s major airport. The built environment factors of interest (i.e., density, safety, trees, hilliness, connectivity, access to parks, and access to shops + services) were primarily collected from government sources and calculated within an 800m distance of each study participant’s home address. Separate two-level growth curve models were run for each research question and type of physical activity (i.e., outdoor, indoor, and total).
Results of multilevel modeling indicated that 1) hot days did not exhibit a significant association with indoor, outdoor, or total physical activity; 2) hot days did not significantly influence the effect of built environment factors on outdoor physical activity; and 3) heat waves did not exhibit a significant association with outdoor, indoor, or total physical activity. With high temperatures not serving as a barrier to physical activity, cities should allocate resources to reducing the risk of exertional heat illness, an adverse health event expected to become more frequent with physical activity promotion and climate change.