Professional football players receive as many as 1,500 hits to the head in a single season, depending on their position. That’s 15,000 in a 10-year playing career, not to mention any blows they received in college, high school, and peewee football. And those hits have consequences: concussions and, according to recent research, permanent brain damage. It’s not just football, either. Hockey, lacrosse, and even sports like cycling and snowboarding are contributing to a growing epidemic of traumatic brain injuries. The CDC estimates that as many as 3.8 million sports-related concussions occur in the U.S. each year. That number includes not only professionals but amateurs of all levels, including children. Perhaps most troubling, the number isn’t going down.
via Popular Science
Image: Travis Rathbone
tl:dr– it rotates to center the impact on the mass of your head so your bean doesn’t spin around in CSF so much.
Unless you also hit another thing?
Definitely one of those cases in which you can cheerfully say Don’t worry Gordon; the chance of a failure cascade scenario is down 12.3 percent from the previous parameters.
http://www.popsci.com/science/article/2012-12/helmet-wars-and-new-helmet-could-protect-us-all?single-page-view=true <...otherwise it's 7 pages or something (but the same comments.)