What bikeshare programs across the United States are discovering is that it's generally wealthier, middle class, individuals who avail themselves of the service, which typically require annual subscription fees. Lower-income individuals simply don't participate, presumably out of economic necessity.

What we also know is that often it is the urban poor who also tend to have a greater incidence of obesity compared to their more well-off neighbors. That obesity brings with it a host of attendant health problems: diabetes, heart disease, hypertension.

As part of an effort to address the problem, the City of Boston, and its famed Boston Medical Center, have taken the unusual step of 'prescribing' bicycles for their patients.

The program works like this. Patients whom their doctors feel will benefit from more physical activity, are written a 'prescription' that entitles them to subsidized membership in the city's Hubway bikeshare program, 13 stations of which are located in low-income neighborhoods. Additionally, reports Boston Magazine:

To qualify for the subsidized Hubway memberships, participants must be Boston residents age 16 or older, and must either be receiving some form of public assistance, or have a household income of no more than 400 percent of the poverty level.

Normally a membership costs $85 annually, but under the program, which presumably is subsidized by the city, qualifying patients pay only $5. For that they get a wireless fob that enables them to access locked bikes, as well as a helmet. Members use the bikes as many times a year as they like as long as the trips are 30 minutes or less.

Since the program has just launched, there is no measurable data on the physiological impact of the program on participants, but the system has seen an 'uptick' in subsidized memberships. The goal is to have a 1,000 low-income members using bikeshare. If they do use it with some regularity, there is evidence from other research that it will have positive health benefits.

In research that I did for a grant proposal to the Gates Foundation last year, I found a number of studies that clearly correlate automobile dependence and our society's multiple health problems. Getting more people on bicycles and out of cars benefits everyone. But getting a people used to riding in an automobile everywhere to take up cycling instead will be harder than just writing a prescription. Still Prescribe-a-Bike surely has to help.

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