To identify epidemiological studies that provided risk estimates for walking on mortality, a review was carried out, based on the US Physical Activity Guidelines Advisory Committee Report (2008),
with additional searches conducted for more recent publications. The review covered studies that specified walking as a separate behaviour and reported a risk for mortality.
In addition, advisory group members were asked to report additional studies. Fifteen studies were identified which reported an association between walking and reduction in all-cause mortality
One of these was a well-conducted and recent meta-analysis of associations between walking and all-cause mortality as well as cardiovascular disease (Hamer and Chida, 2008).
The following 9 studies on mortality among comparable populations identified in the review had controlled in the analysis for other types of physical activity:
+: included in Hamer and Chida (2008)
In a meta-analysis, these studies were combined to calculate an aggregated risk, weighted by sample size. The resulting relative risk estimate was 0.78 (95% confidence interval: 0.64-0.98)
for a walking exposure of 29 minutes seven days a week.
Source:Development of guidance and a practical tool for economic assessment of health effects from walking. Consensus workshop. Background document: Summary of literature reviews and issues for discussion.1-2 July 2010, Oxford, United Kingdom.