If each day Americans substituted driving with walking or cycling for the distance recommended for daily exercise, the United States could reduce oil consumption by between 35 and 38%.... 
52% of Americans want to bicycle more, and 55% would prefer to drive less....More
....and walk more. More than half (54%) of older adults who reported an inhospitable walking, bicycling, and transit environment outside their homes said they would walk, bicycle and take transit more if the streets were improved. About one-quarter of walking trips take place on roads without sidewalks or shoulder, and bike lanes are available for only about 5 percent of bicycle trips. A national survey of pedestrians and bicyclists found that the top complaints were the lack of sidewalks and bikeways.