The connection
between transportation reform -- an emphasis on land use that makes
biking and walking as viable as auto travel for routine trips -- and
health reform is one that's not often made, despite the best efforts of the Obama administration.
Even in traffic-choked Atlanta, denser residential neighborhoods had positive health effects. (Photo: MSNBC)But
a team of researchers led by Lawrence Frank of the University of
British Columbia took a particularly novel approach to the relationship
between transport and health for a study recently published in the
journal Preventive Medicine. For their observations, the group eschewed
Chicago, New York, Portland, or other highly walkable cities in favor
of sprawl-heavy Atlanta.
Frank, Steve Winkelman of D.C.'s Center for Clean Air Policy, and
Michael Greenwald of the Seattle-based firm Urban Design 4 Health used data from Atlanta's SMARTRAQ
survey to map the amount of calories burned by various blends of
walking, transit, and car use. That calorie-burning factor was dubbed
the "energy index."
The "energy index" of Atlantans
increased significantly as their neighborhoods grew denser, according
to the study, and the number of calories they used on motorized travel
shrank in denser, more walkable areas.
But interestingly
enough, the study's density factor only examined residential properties
-- and in neighborhoods where mixed-use development grew, bringing
housing closer to commercial property, the energy used for driving and walking decreased, leaving Atlantans' "energy index" unaffected.
"This
result likely demonstrates that the energy required to travel in a very
mixed land use pattern is lower for both walking and driving — with no
real impact on the relationship between the two modes," the study's
authors wrote.
The authors also noted the significance of
a documented link between dense residential development and public
health in a city known more for its grinding traffic jams and struggling transit:
The
Atlanta region is relatively skewed in terms of walkability, with a low
proportion of survey participants actually walking and limited
variation in urban form. While this presented some difficulty, the
large sample size and oversampling of residents of walkable
neighborhoods allowed for reasonable estimates of association. The fact
that these results emerged in the auto-oriented Atlanta region is an
indication that relationships are robust; associations are expected to
be stronger in regions with higher overall variations in walkability
and/or transit access.
