Recent research shows that walkers or bike commuters are less likely to die than their non active car or public transport using colleagues.
Between April 2007 and December 2010 scientists at the University of Glasgow Institutes of Cardiovascular & Medical Sciences and Health & Wellbeing recruited over half a million people aged 40-69 from 22 locations across the UK. They then selected the 263,000 people who were in employment and did not always work at home.
The report in the British Medical Journal (BMJ) states that 2,430 participants died over a median of 5 years follow-up, with 3,748 cancer and 1110 cardiovascular disease (CVD) cases. Dates and causes of death in England and Wales were held by the National Health Service Information Centre and by the NHS Central Register in Scotland. By analysing this large amount of data, the scientists were able to provide indications of mortality for the different modes of transport used for getting to work, with walkers and bike commuters classed as active, compared with car or public transport as non-active.
At a time when physical activity is declining worldwide, active commuting has been recommended as a practical way of incorporating more physical activity into daily life. There have also been reports that bike commuters are happier and more motivated at work, as well as taking less time off for sickness than their non-active colleagues.
The researchers say that the evidence is limited on the associations of mixed mode commuting (a combination of active and non-active) on health outcomes, but their meta-analysis of 173,146 participants reported that active commuting was associated with a lower risk of adverse cardiovascular outcomes, especially for women.
The analyses were adjusted for sex, age, ethnicity, Townsend deprivation index, comorbidities (longstanding illness, diabetes, hypertension, CVD, cancer, and depression), body mass index (coded as categorical variable based on the World Health Organization classification), smoking, dietary intake (alcohol, fruit and vegetable, red meat, oily fish, poultry, and processed meat), time spent walking for pleasure, time spent undertaking strenuous sport, time spent in light and heavy DIY, level of occupational physical activity, and sedentary behaviour.
After those adjustments, some of the findings were perhaps predictable: cardiorespiratory fitness was highest among bike commuters followed by mix mode bike commuters; and, compared with non-active commuters, walking commuters had higher physical activity – though not cardiorespiratory fitness.
More importantly for campaigns for significant increases in funding for cycling infrastructure and wonderful news for existing bike commuters was the research conclusion that this – along with mixed mode cycle commuting – was associated with a statistically significant lower risk of all cause mortality compared with non-active commuting.
“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, with dose dependent relations for all outcomes. Mixed mode commuting was associated with some benefits but only if the active component comprised cycling. These associations were independent of sex, age, deprivation, ethnicity, smoking status, recreational and occupational physical activity, sedentary behaviour, dietary patterns, and other confounding factors, including body mass index and comorbidities. These results are relevant, because active commuting on a daily basis is an important contributor to total physical activity.”
Bike commuters, and mixed mode bike commuters, had greater overall physical activity and fitness than walking commuters. This finding may reflect the greater exercise intensity of cycling compared with walking. While approximately 90% of bike commuters and approximately 80% of mixed mode cycling commuters achieved current physical activity guidelines, only 54% of walking commuters and approximately 50% of mixed mode walking commuters did; a similar proportion to non-active commuters (51%).
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.