Commuting by bicycle is associated with a substantial decrease in the risk of death from all causes, cancer and cardiovascular disease (CVD), compared with non-active commuting by car or public transport, finds a study in The BMJ.
Walking is also associated with a lower risk of cardiovascular disease, but the risk of death from cancer was no different than non-active commuting, the results show.
Many studies have shown that cycling and walking are linked with health benefits, but there is still some debate about the strength of these associations. So researchers at the University of Glasgow set out to investigate the association between active commuting and incident CVD, cancer, and all cause mortality.
Participants were asked to record the types of transport they used to get to and from work on a typical day. Options included walking, cycling and non-active (car or public transport). During an average five year follow-up period, information on hospital admissions and deaths were recorded.
After adjusting for several influential factors, commuting by walking was associated with a lower risk of CVD incidence and mortality. However, commuting by cycling was associated with the lowest risk of these - as well as lower risks of all cause mortality and cancer.
Mixed-mode commuting (a combination of active and non-active transport) was also associated with some benefits, but only if the active component comprised cycling.
Furthermore, a lower risk for CVD incidence was only evident among the walking commuters who covered more than six miles a week (equivalent to two hours of weekly commuting by walking at a typical pace of three miles an hour).
The researchers point out that this is an observational study, so no firm conclusions can be drawn about cause and effect, and they outline some limitations could have introduced bias.
Nevertheless, they conclude that "the findings, if causal, suggest population health may be improved by policies that increase active commuting, particularly cycling, such as the creation of cycle lanes, cycle hire or purchase schemes, and better provision for cycles on public transport."
In a linked editorial, Professor Lars Bo Andersen at the Western Norwegian University of Applied Sciences, says active commuting has the potential to substantially reduce the costs of cardiovascular disease (estimated at Ģ15bn each year in the UK) and to save many lives.
He argues that the UK has neglected to build infrastructure to promote cycling for decades and the potential for improvements to increase cycling and the safety of cycling is huge.
"The findings from this study are a clear call for political action on active commuting, which has the potential to improve public health by preventing common (and costly) non-communicable diseases," he writes. "A shift from car to more active modes of travel will also decrease traffic in congested city centres and help reduce air pollution, with further benefits for health."