You’re undoubtedly better off wearing a bicycle helmet if you’re on your bike and an accident occurs, and the importance of wearing a helmet increases with the significance of the accident.
But while helmets have come a long way since the strappy leather head coverings some cyclists wore before the 1970s, they still don’t do much to protect us from concussions.
Helmet experts are calling for radically new designs to improve safety.
Studies have found that in an accident, you’re much less likely to suffer a severe brain injury if you’re wearing a helmet than if you’re not, but your odds of experiencing minor brain trauma are similar.
That’s because modern helmets are lined with hard foam. The design can withstand a serious impact, protecting your skull from fracturing against a hard surface such as pavement, but the rigid foam doesn’t absorb as much energy as a softer liner, such as those found in football helmets.
The best protection for a bicyclist would be a helmet made from a softer material thick enough to absorb any impact, but “nobody wants to bike around with a mushroom on their head,” said Mehmet Kurt, who studies head injury prevention at the Stevens Institute of Technology in Hoboken, N.J.
Randy Swart, director of the Bicycle Helmet Safety Institute, a nonprofit based in Arlington, said the transition from round helmets to elliptical or oval-shaped ones in the 1990s was “certainly not an improvement” safety-wise. But people wanted to look like Lance Armstrong.
A round helmet with a smooth surface is preferable, Swart said, because if a helmet snags during an accident, a rider’s head will be whipped around, possibly causing a concussion.
According to Roy Burek, a visiting professor at the Concussion and Traumatic Brain Injury Prevention Group at Cardiff University in Wales, cyclists can face four basic types of brain injury.
Skull fractures and brain bruising result from direct impact and linear energy — the sort you would experience if you fell and hit your head on a curb. Bike helmets protect from these injuries quite well.
But they don’t do much to prevent injuries resulting from rotational energy.
Swart envisions a smooth, round helmet with a softer material that survives more-dramatic impacts but wouldn’t need to be impractically thick.
Burek noted that most bicycle accidents occur at low speeds, so an ideal material for a helmet would be soft when you land at low speeds, to allow the brain to move and thus decrease damage from rotational energy. But that material would also be “smart” — firming up when a high-speed crash occurred, thus preventing a skull fracture.
Burek is hoping for technologies that more closely mimic the scalp. If you press your fingertips against your head and move them around, you can feel that your scalp wiggles around relative to your skull. This wiggle room is important: It helps protect our brains from rotational energy in minor impacts by allowing our heads to move a bit in those cases.
Helmets are not designed to move when you crash, because you really don’t want them falling off.
“We need to come up with materials that don’t collapse head on, but twist and move in different directions like a second scalp,” said Burek. It’s a bit like landing on a water bed instead of a firm mattress.