Cities that host bike-to-work events as their sole effort to increase commuter travel by bicycle may be missing a larger -- perhaps more valuable -- opportunity, according to a study involving the University of Colorado Boulder and led by the University of Colorado Denver.

Researchers at the University of Colorado Boulder and the University of Colorado Denver suggest that local governments use bike-to-work days to find out from participants why they're attending and -- more importantly -- what prevents them from biking more often.

"While single-day promotional events might not be a big influence on people deciding to bike again the next day, bike-to-work day does seem to have the ability to capture a wide range of bicyclists and provide insights into the barriers to increasing their bicycling," Wesley Marshall, co-author of the study and an assistant professor of engineering, said in a statement.

Kevin Krizek, a professor in CU-Boulder's Program in Environmental Design, who also co-authored the study, added that people from all walks of life are coming to bike-to-work events.

"If cities know why people want to get out on their bikes, they can do a better job of building on that information," Krizek said. "Better yet, if cities know what's impeding people from cycling, they can mitigate those obstacles by intervening with new policies."

For the study, more than 1,000 participants from Denver's Bike to Work Day held in June 2012 answered survey questions. The questions measured the types of participants and their behaviors, finding a vast range.

Some of the participants reported they bicycle to work only on the day of the event and others reported commuting by bike year-round. Some were motivated to attend because it was a fun activity while others wanted to raise awareness around the healthy and environmentally friendly mode of transportation. Some had a long history of participation in Bike to Work Day while others did not.

The survey questions also asked participants about their perceived barriers to bicycling. The results included concerns about safety and infrastructure; convenience and weather conditions; and cost and bicycle storage.

"The variety in feedback shows that trying to distill issues into a singular motivation and, subsequently, a singular policy intervention to encourage commuter bicycling is difficult," Krizek said.

Almost all large cities in the United States promote bike-to-work events at least once per year, according to the study. The events commonly consist of free breakfast stations along popular bicycle routes, coordinated group rides, challenges among local businesses, giveaway items such as T-shirts and media coverage.

The findings are detailed in the Journal of Urban Planning and Development.