The network of bicycle lanes will continue to grow across the Twin Cities this summer — a development that may boost some commuters' moods.

Cyclists are the happiest commuters, arriving to work or school in better moods than those who drive solo or ride the bus, according to new research from the University of Minnesota that looked at daily travel behavior and emotional well-being. The findings support the idea, researchers say, that cities should make more kinds of transportation available and appealing.

"In the United States, the car is the most used mode, but the car is not the happiest mode," said Yingling Fan, a professor at the Humphrey School of Public Affairs. "People want to choose the happiest mode, but what we have in our country prevents people from selecting their happiest mode."

Minneapolis, often touted as one of the nation's top bicycling cities, plans to add nearly 7½ miles of protected bikeways this summer. Most of them will connect the University of Minnesota and the surrounding neighborhoods of Como, Marcy-Holmes and Cedar-Riverside where as many as 4,000 people bike daily, making it the city's highest demand area for bicycling.

"We are trying be sure the network is comfortable for all people and make it safer for all seasons and all abilities," said Nathan Koster, a transportation planning manager with Minneapolis Public Works. With protected bike lanes, "we see more riders."

St. Paul works to add 2 to 6 miles of on-street bike lanes each year, said Reuben Collins, transportation engineer for the city. The major projects this year include a new bike trail on Wheelock Parkway and teaming with Dakota County to build a new regional trail connecting Kaposia Landing in West St. Paul with Harriet Island Regional Park. The list for this year could grow because, for the first time, the city has allocated $500,000 specifically for bike projects, Collins said.

"We see the network coming together and making it more possible to get out and ride," he said.

Minneapolis has 129 miles of on-street bikeways and 97 miles of off-street bikeways and St. Paul has 180 miles of paths and on-street lanes, according to the latest figures from each city. As more lanes go in, there remains a tension between motorists, who see the addition of on-street lanes as a way to constrict traffic lanes, and cyclists who say more needs to be done to combat obesity and climate change and make cycling safer.

When Minneapolis announced new bike lanes along 18th Avenue SE., residents who objected were concerned over how much parking would be lost, said Karl Smith, president of the Southeast Como Improvement Association.

"While I agree bikes need to be accommodated, I think we have gone too far in Minneapolis," said Patrick Busch, a bike commuter from south Minneapolis. "They benefit a lucky minority at the expense of ordinary people. Cutting down on the street parking in my neighborhood creates a hardship for people who live here."

Ethan Osten, of St. Paul, agrees that not every street needs a bike lane, but "we need a network of safe bike lanes and bike routes that allow people to get around without fear of death or serious injury. We are a long way from that still," he said.

Some hearty cyclists ride year-round in Minnesota, but there's a bicycling boom each spring when the snow melts and temperatures rise. The annual "30 Days of Biking" challenge takes place in April, and May is National Bike Month, according to the League of American Bicyclists. About 4% of commuters pedal to work in Minneapolis, as do 2% of commuters in St. Paul, according to census data.

Researchers' findings on commuter happiness came as no surprise to Chris Lynch, 44, who has been riding his bike from his northeast Minneapolis home to his IT job at the U for the past 4 years.

"I have that extra burst of oxygen when I arrive," he said. "I'm not stuck in stop-and-go traffic. With biking you have time to be with your own thoughts and exercise."

Gordy Moore, 24, who often bikes but sometimes drives or takes transit from the Whittier neighborhood in south Minneapolis to his job at a nonprofit in northeast Minneapolis, agreed.

"Flying down a hill or making steady progress in a bike lane is much more pleasant than sitting in traffic on 35W," he said.

Fan, along with a colleague from Northwest University in China, used data from the 2012-2013 American Time Use Survey to look how people viewed their journeys. Drivers may choose to take their car because it is more convenient or allows for faster travel, but not necessarily because they like driving, Fan said. Bicyclists, however, choose biking because they like cycling and because it helps reduce stress and allows them to focus on the task at hand.

Biking brought the highest levels of happiness, but other factors, including trip length and whether they were traveling with family and friends, also influenced commuters' emotions.

"Transportation plays an important role in our daily lives and Americans spend a significant amount of time per day on daily trips," said Fan. "It is important to know whether some trip types are more likely to induce positive emotions after controlling for personal factors."

Tim Harlow • 612-673-7768