It's an odd quirk of bike racing that the sport would be so environmentally taxing. But with an armada of support vehicles driving every route—about 1,500 cars, trucks, and motorcycles crawling over 2,000-plus miles in the Tour de France alone—the emissions add up. So this year, the domestic Kodak Gallery Pro Cycling Team, presented by Sierra Nevada Brewing Co. (the sponsorship dollars add up, too), will become the first carbon-neutral pro bike squad, purchasing enough wind-energy credits to offset all of the emissions the team and staff will generate. "Nobody recognizes the impact of air pollution more than a cyclist who's out on the road five hours a day," says marketing director Rob O'Dea.

While Kodak Gallery is a rarity among individual teams, in the larger world of sporting events, the concept is running full-throttle, so to speak. The Olympics and the World Cup have taken major steps to reduce their footprints, and the NFL has relied on renewable-energy credits, recycling, and tree planting to green up every Super Bowl since 2005. "One event won't make the difference," says Jack Groh, director of the NFL's Environmental Program. "But it may trigger interest."

We just hope NASCAR's paying attention.