Football helmets are not effective at preventing concussions, a new study found.
They are important for preventing skull fractures, but researchers from Florida State University wanted to investigate the strength and safety of 10 popular football helmet designs against concussions as well.
The experiment design was a standard drop test system, where motion sensors were placed on the heads of crash test dummies that were wearing helmets as well dummies without. Researchers aimed repeated 12 mile-per-hour impacts at the dummies, measuring the heads' linear and rotational responses.
Overall, the results revealed that compared to not wearing a helmet, wearing one only reduced mild traumatic brain injury by 20 percent. What's more, the researchers noticed that the helmets that offered the least amount of protection were also the most popular among football players.
In particular, the Adams a2000 design had the best protection against concussion but the worst protection against closed head injury, and the Schutt Air Advantage helmet had the worst overall protection.
Football helmets are effective against linear impacts, reducing the risk of skull fracture by 60 to 70 percent.
The study's team stress that wearing a helmet is better than not wearing one, but that players should take into account just how little helmets do to prevent mild traumatic brain injury.
"Biomechanics researchers have long understood that rotational forces, not linear forces, are responsible for serious brain damage including concussion, brain injury complications and brain bleeds," said Dr. Frank Condi of the Florida Center for Headache and Sports Neurology and the Florida State University College of Medicine in a statement. "Yet generations of football and other sports participants have been under the assumption that their brains are protected by their investment in headwear protection."