Walk into any fitness facility and you are likely to find more treadmills on the floor than stationary bikes.  Take a look outside and you will see a similar trend, with more individuals walking or running for exercise rather than riding a bike. It's possible that this bias is a result of a lack of understanding regarding the health benefits that are associated with bicycling. This trend may also be partly explained by the fact that the infrastructure of the United States' roadways are less "bike friendly" in comparison to other countries in which barrier-protected and bicycle-exclusive tracks are present. 

A study published in the June 28, 2010 issue of the Archives of Internal Medicine, evaluated and compared the effects of bike riding and walking on weight gain in premenopausal women.  The results indicated that bike riding is associated with less weight gain in premenopausal women, as is with brisk walking - but not slow walking; and, that an inverse dose-response relationship exists (i.e., the more time spent biking, the less the weight gain). 

This investigation was part of the Nurses Health Study II (NHSII) and involved examining the exercise habits (with respect to biking and brisk and slow walking) and weight gain trends of 18, 414 healthy premenopausal female nurses from the United States.  During this 16-year follow-up study, exercise and sedentary behaviors were obtained from questionnaires completed by the subjects in 1989 and 2005.  Body weight values were derived from answers to biennial questionnaires completed by the women.

Researchers found that women who were not bicycle riders in 1989 but increased their participation in this form of exercise by 2005 had gained less weight than those individuals who remained nonbikers.  Furthermore, the more time spent biking, the lower the amount of weight gained.  Conversley, gains in weight increased in women who were bikers in 1989 but had stopped or decreased their participation in bike riding by 2005. Effects were more pronounced for women who weighed more at baseline than for their leaner counterparts.  Brisk walking had similiar results, but not slow walking.

The investigators note that these findings are significant since brisk walking may be too difficult for individuals with physical limitations, such as rheumatoid arthritis.  Thus, biking would be an acceptable alternative since slow walking was not associated with attenuated gains in weight. The researchers also suggest that future research efforts focus on determining the type of environments and infrastructure that are most conducive to bike riding, especially for women.

Source:
ARCH INTERN MED/VOL 170 (NO. 12), June 28, 2010:1050-1056, "Bicycle Riding, Walking, and Weight Gain in Premenopausal Women," Lusk, A.C.