Health risks are a serious occupational hazard for professional athletes. Injuries can occur without warning and bring once-promising careers to an abrupt end. Their effects can also worsen over time and cause damage that lasts the rest of a player’s life. Head injuries, in particular, are suspected to bring on a wide range of neurological disorders, such as depression and dementia, even after a player’s athletic career has ended. Unlike a structural injury that involves a ligament tear or a shoulder sprain, brain injuries are not always apparent or detectable, so athletes sometimes continue playing without knowing they are at risk for further debilitating outcomes.

Fortunately, recent technological developments are currently being tested in the NFL and NHL to quantitatively detect when a blow to a player’s head may warrant a visit by medical staff. A story in TIME magazine in July presented research showing that 35 percent of the retired NFL players in the study displayed signs of a mild form of dementia that can lead to Alzheimer’s disease, a high number for that age group. The NHL is also assembling many of its past players for similar studies to provide data leading to a better understanding of the causes behind concussions in the short term and life-altering brain injuries in the long term. This information will give researchers more material on which to base future studies. Meanwhile, a number of companies have already devised sensors that can be worn inside a helmet to provide real-time data on the severity of hits to the head

An American company called Battle Sports Science, the Canadian company Impakt Protective, Inc., and a University of Alberta research team are testing their designs on junior hockey and NHL players this season. Essentially, each device is programmed with a threshold measured in G-force, or the pressure exerted on the helmet. When the sensor detects pressure greater than the threshold, a warning light is either displayed on the helmet itself or relayed to a hand-held device up to 100 meters away. The idea is not necessarily to determine absolutely if a player has sustained a concussion. As assistant professor Martin Mrazik puts it, “This takes the grey zone out and says, ‘We know you just suffered a significant hit to the head,’ and that would allow medical staff to do an evaluation of the player.”

The technology is promising, but obstacles remain. For instance, there is no agreed-upon threshold for what amount of force will deliver a concussion. Another problem is that injured players sometimes deny feeling symptoms of a concussion to avoid being pulled from the game. Senior Harvard QB Andrew Hatch expresses the football mentality: “There’s definitely pressure to come back. There’s the expectation that if you seem you can play, you should do everything you can.”

Sensor manufacturers acknowledge there is still testing to be done before the products hit the market. Even so, it is comforting to know that the implementation of these devices is approaching the neighborhood rink and the professional sports arenas. If adapted throughout various sports leagues where concussions are a problem (namely hockey and football), concussion warning systems could ease concerns among players, teams, fans, and families about the threat of brain injury and adequate protection for those who participate in violent sports.