While the health benefits of bike share programs may seem obvious (more exercise equals reduced obesity, heart disease, type II diabetes, and other diseases cased by sedentary lifestyles), hard data to support that assertion is helpful when it comes to persuading decision makers to invest funds in building such systems.
Such data may also provide useful insights into how to structure such programs to maximize benefit. For example, when health benefits are canceled out by fatalities in certain populations and not others, perhaps it’s time to take a look at how those cyclists are interacting with roadways.
That’s why a study on the health impacts of London’s Bixi program, published in February on the British Medical Journal, is a valuable add to a growing body of literature quantifying the costs and benefits of bike share programs.
While little empirical data exists to demonstrate bike share’s health impacts, modeling studies combining demographic characteristics with the known health benefits of exercise can estimate impacts at the population level. A previous study of Barcelona’s system predicted reduced mortality in the overall population with a reduction of 12 deaths .
The February study also takes a predictive approach, modeling the expected health benefits of 587,607 bike share participants in London’s Bixi program. But it takes the analysis a step further by parsing the outcomes by sex and age, with some interesting findings.
The study predicts that while the Bixi program has overall health benefits for the population, the benefits are stronger for men than for women and for older users than younger ones.
Older men are most likely derive benefits because the positive impact of exercise is so important to staving off disease in that population, according to the study.
The potential benefits of cycling may even be negative for younger cyclists (15-29 years), according to the study, because the risk of fatality by collision may outweigh the benefit of exercise in young, healthy individuals. Female cyclists see a higher road collision fatality rate, which negated the benefit in the female population.
It’s important to note that the study compares biking to trips otherwise made on foot or via public transportation; such a comparison in an automotive-dependent city would likely be very different.
The data on fatalities drew from central London, where heavy vehicles were a major culprit in the fatalities of female cyclists. The study points to a need to examine solutions that will enable all cyclists to realize the potential health benefits of bike share.