Changes in neighborhood walking are related to changes in perceptions of environmental attributes.

<b>Background</b>: Several studies have found significant cross-sectional associations of perceived environmental attributes with physical activity behaviors. Prospective relations with environmental factors have been examined for vigorous activity, but not for the moderate-intensity activities that environmental and policy initiatives are being designed to influence. <b>Purpose</b>: To examine prospective associations of changes in perceptions of local environmental attributes with changes in neighborhood walking. <b>Methods</b>: Baseline and 10-week follow-up telephone interviews with 512 adults (49% men). <b>Results</b>: Men who reported positive changes in aesthetics and convenience were twice as likely to in-crease their walking. Women who reported positive changes in convenience were more than twice as likely to have increased their walking. There were contrasting findings for men and women who reported traffic as less of a problem: Men were 61% less likely to have increased walking; however. women were 76% more likely to have done so. <b>Conclusions</b>: Further studies are needed to determine the possibly causal nature of such environ-ment-behavior relations and to elucidate relevant gender differences. Such evidence will provide underpinnings for public health initiatives to increase participation in physical activity.<br />