Texans famously love their cars. And the proliferation of suburbs and exurbs must make the state the ideal place to study the impact of long commute times on health and physical fitness.

Researchers from the Washington University in St. Louis and the Cooper Institute have done just that, tracking 4,297 commuting Texans from the Austin and Dallas-Fort Worth metro areas. They found that those who commuted longer distances weighed more and had decreased “cardiorespiratory fitness.”

For the study, published in the June issue of American Journal of Preventive Medicine, researchers measured the distance commuters drove to work and tracked their body mass index, waist circumference, fasting glucose levels, cholesterol, and blood pressure, and other indicators of metabolic risk.

“Commuters who log 16 or more miles each way on their daily haul to the job tend to pack plumper paunches and post higher blood pressure when compared to those with shorter excursions, according to the first research exploring the intersection of travel distances and health impacts.” Bill Briggs wrote at MSNBC’s Vitals blog.

What are some of the reasons for these bulging waistlines? Well, those who spend longer in the car have less time to exercise. And long, congested commutes lead to increased stress levels.

A full 33 percent of commuters drive more than sixteen miles to work, according to the U.S. Department of Transportation. At the Atlantic Cities, Nate Berg notes that the Centers for Disease Control says more than 35 percent of American adults are obese. 

Berg urged scientists to conduct further studies on the topic:

Long commutes were already easy to loathe, but there’s still room for further research on this subject. The authors note that future studies would be needed to fully understand whether and how sedentary time during commuting affects health. For example, how is sitting in a car for an hour on your way to work different from sitting in your chair for an hour when you’re at work? Or sitting on your couch? Or, instead of sitting in a driver’s seat, sitting in a bus seat?

Fitsugar offered five ways to make your commute less harmful, including carpooling, eating breakfast, and carving out time for the gym.