With football-related concussions in the news—one-third of NFL players suffer from brain trauma—and a nation of runners eager to dodge injuries, a new breed of wearable fitness tools aims to not only track calories burned but also blows to the head and strain on the calves.
The challenge these devices’ makers face, according to them and other experts, is providing reliable alerts to help keep athletes healthy without unnecessarily sounding the warning bells when they’re playing safely.
"You can’t just bring a person into a lab and slam stuff into their head and see what happens," says Benjamin Harvatine, the cofounder and CEO of Jolt, which is in the midst of a Kickstarter campaign to fund a clip-on head impact monitoring device.
The idea for the Jolt sensor came to Harvatine after he sustained a serious concussion himself in college wrestling practice but, attributing his dizziness to hunger or dehydration, continued to wrestle, sustaining more blows to the head throughout the session.
"When I went to stand up, I couldn’t really stand up right," he says. The most severe symptoms persisted for about five months. "It was a situation where I felt like I would have really benefitted from something that would really quantify, was I dizzy because of head impact, or not?"
Jolt’s sensor, which is designed to be mounted on a helmet, headband, or other athletic headgear, tracks the level of head impact athletes sustain and relays those measurements in real time to a companion smartphone app, so coaches or parents of younger athletes can see what’s happening to players’ heads.
The app also includes a concussion symptom checklist and cognitive assessment test coaches can give players to see if their thinking is clouded after impact. Jolt will encourage coaches to give the players the tests regularly, even when they haven’t taken any serious blows to the head, to help establish a baseline and potentially detect any cumulative effects of smaller injuries.
"Every day after practice, or once a week, they can take this test in the app," Harvatine says. "We can start to watch this data, and see if we pick up on any trends medical folks haven’t picked up on yet."
Similarly, a helmet insert from Reebok, called the Checklight, uses green, yellow, and red lights to quickly signal when a player has taken a moderate, heavy, or no impact to the brain. When the light glows yellow or red, Reebok recommends the player get checked out, says Paul Litchfield, head of Reebok Advanced Concepts.
"Go through a screening process that is appropriate to whatever environment you’re in," he advises athletes, explaining the device uses a formula based on linear and rotational forces applied to the head and other factors.
And other devices can measure potentially harmful forces applied to the rest of the body. GestureLogic’s LEO LegBand, which successfully raised more than $140,000 in an Indiegogo effort concluded last month, can warn runners and cyclists to reduce the level of impact on their legs, or to stop and take a drink when they become dehydrated. Since the leg band uploads user data to GestureLogic’s cloud, the company says it should grow better at warning of injuries over time.
Boogio cofounder Jose Torres says the company’s devices, currently available for preorder, should be able to establish a baseline of healthy movements for individual athletes and warn them when they step out of that safe zone.
"You can see this is too much weight, or you’re tired, or your posture is incorrect," he says.
And Scribe Labs’ runScribe inserts track technique, distance, and speed over time and even help runners figure out which shoes are healthiest for them, says CEO Tim Clark.
"I actually managed to find what shoes I should be in, and they were completely not the shoes that the guys in the running shoe stores were trying to put me in," he says.
Of course, all of these device makers emphasize their products aren’t medical-grade equipment; they’re not meant to diagnose particular injuries, or substitute for the advice of a doctor, trainer, or physical therapist. With head injuries, in particular, that’s inevitable, since there are no hard and fast rules for diagnosing a concussion.
"The medical community does not have the exact definition of what thresholds would cause injury and what thresholds would not cause injury," says Reebok’s Litchfield.
Studies have shown athletes avoiding apparent concussions after impacts hundreds of times the force of gravity, while others were concussed after milder impacts, says Thomas Talavage, a Purdue University engineering professor and medical imaging expert who’s studied head injuries and techniques for detecting them.
"The truth is is that there is no definable threshold beyond which you’re certain or even necessarily likely to get a concussion," he says, arguing that sensors would get more accurate results monitoring the full range of impact sustained by an athlete over time.
"You almost certainly require some level of modeling of what have been the most recent exposures for a given athlete," he says.
That’s a goal to which most of these device makers aspire, with many of them eager to collect user data to help scientists develop new and better models of what causes injury.
"For us, we see the data we’re storing, capturing, and analyzing as something that’s very valuable," says Jolt’s Harvatine.
Jolt and other sensor makers also plan to update their devices and apps with code and thresholds based on ongoing medical research, he says.
"With any device that has any sort of connectivity like for ours, we can push over-the-air updates," he says. "All of these devices will be continually monitoring the latest medical research in the area."