Just a few short trips by bike each week will make a huge difference in your health and your city's air quality.

Consider this: Half of all car trips in the United States are for distances of less than 2.5 miles. That's a short bike ride skipped for the sake of circling the parking lot to find an open space. Cycle those trips instead and you don't have to get religion to see the benefits, including weight loss, better heart health, longer life, and more money.

And why not give it a shot for a few weeks? A third of Americans get no exercise at all. More than 8 percent of us suffer from asthma, and 10 million adult Americans have chronic obstructive pulmonary disease, a respiratory disease brought on, in part, by low levels of air pollution. Our cars worsen these conditions by releasing gases that combine to make ozone and particulates, both of which increase the risk of asthma attacks and other lung complaints.

For a study published in the journal Environmental Health Perspectives, researchers at the University of Wisconsin, Madison checked out the benefits of cycling for residents of 11 Midwestern cities, if they replaced short car trips under 2.5 miles with bicycle trips. For the entire Midwestern region covered by their study, they found that a shift to biking would result in 1,295 fewer deaths per year, 860 fewer cases of non-fatal heart attacks, and 2,500 fewer asthma attacks.

They also estimated the combined benefits from better air quality and physical fitness would surpass $8.7 billion per year for the region's 31.3 million people. What's more, eliminating so many miles driven would provide significant greenhouse-gas savings—to the tune of 3.9 billion pounds of carbon dioxide.

So take advantage of our globally warmed winter and make these short-haul trips part of a bike-ride to work—it's better for you, your neighbors, and the planet. Here are some basics to bike commuting:

• Commit to biking just a few days a week.
• Buy a good commuting bike—no need for a $2,000 racing bike when a $400 commuter will serve you better.
• Stay seen—use lights and wear bright colors and reflective clothing.
• Leave early—give yourself time to get to work.
• Don't carry too much, and buy a basket or paniers for what you do need; backpacks just weigh you down and make you sweat too much.
• Stow baby wipes and deodorant at work.
• Buy a good lock, preferably from a company that will replace your bike, up to a certain value, in the event that it gets stolen.

And if bike commuting just isn't practical for you, find yourself a nice trail and ride on the weekends. A recent study out of England showed that children who rode bikes just for fun were 40 to 42 percent more likely to be physically fit (according to a standard test) than their non-riding peers.