Archive for the ‘Health’ Category

Evaluating the Health Benefit of Bicycle Helmet Laws

Sunday, April 19th, 2009

We reported earlier the need for additional study of Australia’s mandatory bicycle helmet law. That’s been done.

An interesting study was released last month which models the health benefits of Australia’s mandatory bicycle helmet law.

The bottom line: Australia’s mandatory bicycle helmet law has adversely affected overall health.

A model is developed which permits the quantitative evaluation of the benefit of bicycle helmet laws. The efficacy of the law is evaluated in terms of the percentage drop in bicycling, the percentage increase in the cost of an accident when not wearing a helmet, and a quantity here called the “bicycling beta.” The approach balances the health benefits of increased safety against the health costs due to decreased cycling.

Using estimates suggested in the literature of the health benefits of cycling, accident rates and reductions in cycling, suggest helmets laws are counterproductive in terms of net health. The model serves to focus the bicycle helmet law debate on overall health as function of key parameters: cycle use, accident rates, helmet protection rates, exercise and environmental benefits.

This study also estimated the health impact of a mandatory U.S. helmet law would cost approximately $5 billion per year.

The idea of a Michigan state law requiring bicycle helmets came up during a 2004 Senate hearing while we were updating Michigan’s bicycle laws. I noted that helmets use should be voluntary. The kid that rides his bike with or without a helmet is far healthier than the kid that doesn’t ride a bike at all. We shouldn’t throw up barriers to having more kids riding bicycles.

Fortunately Michigan does not have a mandatory bicycle helmet law, but some Michigan communities do:

  • Adrian (under 15)
  • E. Grand Rapids (under 18)
  • Farmington Hills (under 16)
  • Kensington Metropark (all ages)

Among these, the Kensington helmet requirement is quirky.

The Metroparks don’t require helmets. Milford Township has an ordinance that applies to bicyclists only at Kensington while riding on the paved trail where it’s 10 feet wide. And the helmet must meet the ANSI standard, eventhough there was no ANSI helmet standard from 1998 through 2003.

It appears you do not need to wear a helmet while bicycling on the roads or any unpaved designated bike trails at Kensington.

Duh! Obesity and Transportation are Linked

Monday, January 5th, 2009
by Austrian artist Erwin Wurm

by Austrian artist Erwin Wurm

A recent study by the University of Tennessee’s Obesity Research Center documents the relationship between obesity rates and active transportation (i.e. biking, walking, and public transit.)

The study’s lead author, David Bassett, co-director of the Obesity Research Center and professor in the Department of Exercise, Sport and Leisure Studies, said more people are thinking about transportation issues to save gas and money. On top of that, Americans are obsessed with losing weight, and the latest statistics show about one in three U.S. adults are obese.

“Many people blame this on things like technology, TV, Internet and sedentary jobs, but what we found was that there are other industrialized nations who have similar, high standards of living, who do not suffer from obesity to nearly the same extent that the U.S. does,” he said. “I truly believe that the transportation modes in various countries are important in explaining international differences in obesity rates.”

This study’s results are just another justification for building more biking and walking infrastructure in Metro Detroit.

And it also supports the Safe Routes to School concept, especially given the amount of childhood obesity in Michigan.  In 2007, 12% of children in Michigan were obese (>20% overweight.)

Unfortunately many of those responsible for transportation decisions have little experience or background in health.  Improving community health is not on their radar.  But one thing road engineers are good are is understanding numbers — and this study provides them.

  • In 2000, Europeans walked an average of 239 miles per person per year.  Americans walked 88 miles. And while Europeans biked 118 miles per year on average, Americans rode only 25 miles.
  • In Atlanta, every hour per day spent driving was associated with a 6 percent increase in the likelihood of being obese.

One caveat is the results do not prove causality.  However, the authors note the results “suggest that active transportation could be one of the factors that explain international differences in obesity rates.”

Safe Routes to School

Thursday, December 11th, 2008

srts_logo1In 1969, 42 percent of students walked or bicycled to school.

In 2001, 16 percent of students between the ages of 5 and 15 walked or bicycled to or from school.  Less than half of students living within a mile of school walk or bike to school even once a week.

Is there any wonder there’s a child obesity epidemic?

The Safe Routes to School (SR2S) state and federal programs are aimed at reversing those trends.  The program pursues 5 – E’s to help get more kids walking and biking to school:  engineering, enforcement, encouragement, education and evaluation.

The good news is there’s SR2S grant money to help schools pursue this.  M-DOT is projecting over $6 million in grants for 2009.  Over 350 Michigan schools are already participating.

Tonight some of us gave a presentation to the School Board of Royal Oak about middle school science lesson plans and encouraged them to participate in this program.  It certainly seemed to many in attendance that this was a good idea.

Coincidentally, the school board meeting was held in my old (and now closed) elementary school.  I hadn’t been in the building for 25 years .  I noted that I almost always walked to school back then.

What can you do to help get your school district interested in SR2S?

Fortunately the Michigan SR2S and the National Center for SR2S are great web sites and a great place to get better acquainted with the program.  And since this program addresses student health and safety — and provides funding — it should be a relatively easy sell.

There’s also the upcoming annual statewide SR2S meeting on Monday, January 26, 2009 and it’s free.  It may be a simple “ask” to get a school representative at that meeting.

Mandatory Bicycle Helmets Laws

Saturday, December 6th, 2008
Photo by Dan Burden /

Photo by Dan Burden /

Laws that require bicyclists to use helmets are certainly the result of good intentions — making cycling safer. Unfortunately these laws result in reduced health and safety by discouraging cycling.

First, let’s look at Australia, where a mandatory bicycle helmet law went into effect in 1992.  The results are “ambiguous” according to a report from the Bicycle Federation of Australia

Any countries or jurisdictions considering the introduction of compulsory helmet wearing laws should look very closely at the available data to see if it still supports such a move in light of the ambiguous Australian experience. It is essential that reliable evaluation methodologies be recognised, and the common shortcomings of both databases and interpretation which bedevilled the early Australian evaluations be avoided.

Resources devoted, on the European model, to improving facilities for cyclists and to reducing urban speed limits are likely to be far more cost-effective than the introduction of helmet legislation. These measures must be considered as a valid alternative to helmet legislation or as a vital and integral part of such legislation.

It is crucial that a good and extensive data base of regional or national hospital admissions, and if possible hospital casualty department treatments be assembled for the decade or so preceding the legislation. This is needed to allow a reliable comparison with data collected after the introduction of any legislation.

Note that the second paragraph reiterates a point we’ve made before.  We’d make bicycling much safer in Michigan if we devoted more time promoting safe bicycle facilties (e.g. bike lanes) rather than helmets.

This conclusion is also supported by an article published in the Journal of the Royal Society of Medicine:

In both Western Australia and New Zealand, helmet use increased from negligible levels to more than 80% in around eight years, yet follow-up studies did not show long-term benefits for the cyclist populations relative to control groups. Study of injury trends in each state of Australia for the period when helmet laws were passed shows stable characteristics, revealing no evidence of extra prevention due to legislation coming into force.

And this same article notes that mandatory helmet laws significantly discourage cycling at a time when we need more people getting exercise.

The one clear population-level effect of helmet laws that has been widely reported is the deterrence of cycling. In every case where data are available, cycle use has fallen by 25-50% when a helmet law was enforced. This has a direct consequence on the risk of death in cycling. Study of international evidence points to a reliable relationship between the amount of cycling and the risk in cycling12-a power-law relationship with an index value of around 0.4. A fall in cycle use of 50% would increase risk per cyclist by more than 50%, whereas an increase in cycling of 100% would reduce the risk by almost 40%. Public health would benefit substantially. A report by the Commons Select Committee on Health specifically cited a resurgence in cycling as ‘probably the most effective response’ that could be made to address the obesity ‘time bomb’. It is most likely that road deaths would fall overall; even in Britain one hour of cycle use is not more likely to result in a road death than one hour of driving, because the third-party risk from cycling is so low.

The last point about third-parties is an interesting one.  Motor vehicle crashes with pedestrians and cyclists too often result in death.  Cycling crashes do not.  The more we can promote bicycle use in place of motor vehicle use, the more we can improve overall safety.

This is especially true in our downtowns where there is a greater concentration of pedestrians.

And one way of encouraging a shift from car use to bike use is through bike rentals.  Paris is the world leader in bike rentals.  They have over 20,000 rental bikes throughout their city.  The bike rentals are free for the first half-hour.  One only needs a credit card to place a deposit on the bicycle — and it’s fully automated.  There is a bike rental station about every 1,000 feet so they’re never too far away.

In it’s first year, there were 27.5 million trips made on these Paris bikes, or about 120,000 per day.

What did it cost Paris?  Zero.  An advertiser paid for the system and subsidizes its use in exchange for advertising space.

Bikes Belong has an very cool video demonstration of this Paris system.

It’s been so successful that other cities such as Washington D.C. and Chicago are pursuing similar systems.

So what does this have to do with mandatory helmet laws?  There is no reliable and safe way to rent helmets with these bike rental systems.

From Austrailia to Israel, mandatory bicycle helmet laws are a significant obstacle to these bicycle rentals.

Overall, the safety results are quite conclusive.  Mandatory bike helmet laws are no substitute for designing our roads for safe bicycling and making it easy for people to choose bicycling.

How the Dutch do Safe Routes to School

Tuesday, May 6th, 2008

This video show families and kids biking and walking to school. It’s simply amazing to see such a high level of participation — and all of these kids developing a positive healthy lifestyle. It’s a huge contrast from schools in Metro Detroit which are often clogged with parents chauffeuring their children to school, causing area traffic congestion, and fostering a dependence on commuting by car rather than by biking or walking.

This video was taken by David Hembrow who adds “It’s important to realize that this is not an exceptional day, nor an exceptional school. Dutch children [are] everywhere, every day travel like this.”

Additional resources: National Center for Safe Routes to School, Michigan Safe Routes to School