T op D o w n : S a m R ic h e / M C T v ia G ett y I m ages ; N Y D aily N e w s v ia G ett y I m ages ; h el m et illustrations b y gra h a m m urdoc h
The Fallen Junior Seau’s suicide in 2012 heightened the controversy around head trauma in athletes. Colts receiver Austin Collie [above] received three game-ending concussions in 2010 before he was benched for the season.
accurate picture of what’s happening inside the head. For generations, doctors believed that concussions were a sort of bruising of the brain’s gray matter at the site of impact and on the opposite side, where the brain presumably bounced off the skull. The reality is not nearly that simple: Concussions happen deep in the brain’s white matter when forces transmitted from a big blow strain nerve cells and their connections, the axons. To understand how that happens, it’s important to recognize that different types of forces—linear and rotational acceleration—act on the brain in any physical trauma. Linear acceleration is exactly what it sounds like, a straight-line force that begins at the point of impact. It causes skull fracture, which makes perfect sense: You hit the bone hard enough, it breaks. Rotational acceleration is less intuitive. It occurs most acutely during angular impacts, or those in which force is not directed at the brain’s center of gravity. You don’t have to know much about football or hockey to realize that rotation is a factor in a whole lot of hits. “Think about it,” says Robert Cantu, a neurosurgeon at Boston University School of Medicine and the author of 29 books on neurology and sports medicine. “Because most hits are off-center and because our heads are not square, most of the accelerations in the head are going to be rotational.” Further complicating matters, the human brain is basically an irregularly shaped blob of Jell-O sitting
Crash Course The helmet market is booming. What sets the new products apart?
Riddell 360 The official NFL helmet partner since 1989, Riddell launched the 360 in 2011. It has extra padding around the front and sides of the head, and the company’s signature Concussion Reducing Technology, which adds even more padding. Yet for all that foam, most experts say it does little to address rotational forces, the primary cause of concussions.
Xenith X2 Made by the nine-year-old helmet company Xenith, the X2 replaces foam padding with an array of air-filled cylinders that compress upon impact by releasing air through tiny holes. The harder the hit, the stiffer the response. Such adaptive cushioning can protect against both lower-level and higher-level forces but still does little to address rotation.
Schutt Ion 4D Made with thermoplastic urethane cushioning that performs consistently even in extreme weather, the Ion 4D, Schutt says, “is designed with the intent to reduce the risk of concussions.” Yet the specs don’t mention rotational force, and a 2011 promotional video dismisses the idea that frequent lesser impacts are as dangerous as the rare violent one, calling it “unproven.”
Rawlings Quantum Plus Better known for its baseball helmets, Rawlings introduced a line of football helmets a few years ago that, like Riddell’s, relies on what’s called large-offset design—in other words, increased distance between the head and the shell in order to make more room for extra padding.
SGH Helmet This startup from the self-proclaimed Godfather of Safety, motorsportsequipment legend Bill Simpson, says it makes the lightest helmet on the market. Its shell includes Kevlar and carbon fiber; its padding consists of a single layer of a proprietary composite whose makeup Simpson won’t divulge until it is patented.
january 2013
Guardian Cap Developed by Atlanta engineer Lee Hanson, the Guardian Cap is a padded sock worn over a standard helmet. Critics say the Guardian could get caught during impact, causing neck injuries and exacerbating rotation. Hanson says the sock would just slip off. As for the obvious aesthetic issues, he says the Guardian is meant only for practice, not games.
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