Melbourne, Australia – Commuting to work by car is associated with weight gain even among physically active adults, concludes a new study from the Baker IDI Heart and Diabetes Institute.

Researchers examined 822 Australians over a four-year period, dividing them into three groups: non-car commuters, occasional car commuters and daily car commuters. The people who drove to work gained weight, with daily commuters gaining the most – roughly 4 pounds during the study, according to the study abstract.

The only people who did not gain weight were those who exercised weekly and did not drive to work.

The study was published online Jan. 8 in the American Journal of Preventive Medicine.