03/31/2009 03:46 am ET Updated May 25, 2011

Mass Transit Makes You Skinny

The first thing you'll notice anecdotally when you leave the U.S. for most European countries is that there are fewer fat people. Not none. Just fewer. And while you speculate on the many variables that might make that so, researchers are starting to draw associations between healthy mass transit systems in cities and health(ier) bodies in the body politic.

The University of British Columbia (UBC) looked at 4,156 user surveys from Atlanta, Georgia and discovered that transit trips had a higher association to fitness than car trips. The increase in physical activity associated with mass transit trips - walking to the bus stop and back, for example - seems pretty obvious.

And some people would object that studying this kind of thing is a waste of taxpayer (in this case, Canadian) taxpayer funds. Yet it is just this kind of data that can help us shift our design of cities to more friendly, healthy, and sustainable centers.

Science Codex reports that the UBC researchers found that people who take public transport are as much as three times more likely to meet daily minimums of physical activity suggested by the Heart and Stroke Foundation of Canada than those who don't.

"You don't necessarily have to rebuild communities or make major investments in infrastructure to promote public health," says UBC Professor Lawrence Frank. "There are things we can do in the interim, such as encourage people to drive less, and adapt their lifestyles which will get people more physically active and generate fewer greenhouse gasses."

The guidelines recommend 30 minutes per day of moderate exercise, which doesn't seem like a hard goal to meet. But the researchers found that those who drove the most were also the least likely to meet the guidelines.

Making transit incentives like the one in the proposed "cash for clunkers" bill (and don't forget bikes as a form of transit!) would have GHG reduction benefits and, from what the UBC researchers found, health benefits as well.

However, UBC's review was based on interviews from 2001 and 2002. It would be supremely interesting to see research measuring (any) immediate benefits from the recent rise in public transit ridership. In Sydney, for example, citizens took 22 million more rides on public transport in 2008 than the previous year, and one planning expert said this is part of a long-term global trend.

If we could gather data on the benefits to public health - shouldn't that be factored in when considering more and better mass transit projects? Philip James, head of the International Obesity Task force, thinks so.

Instead of the "obesogenic" environment planners have created with current car-centric cities, James says we need more "slim" cities like Oslo where the built environment discourages cars and encourages walking and cycling. Instead of expecting people to constantly work against the cues our built environment gives, perhaps we should adapt our environment to make us a bit more happy, healthy, and wise.

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::Lady Liberty Dumps the Car and Marries Mass Transit
::Los Angeles on the Verge of the Nation's Best Mass Transit?
::PBS Examines Stimulus Package's Impact on Local Transit
::Carrot 0, Stick 1: Gas Prices Cause Boom in Bikes, Transit
::Survey: Freedom of Mobility or Public Transport?
::Zero Emissions Urban Mass Transport: The Buscycle