Armchair football fans view clear evidence that technology is influencing their favorite sport. They watch as TV networks mark first downs with computer-generated yellow lines and scroll instant game scores and myriad other statistics across the top and bottom of their screens.
But more and more, technology is also influencing what's happening on the field among players and coaches. Two new technologies aimed at making the sport safer for athletes, and a play-calling computer that could give a coach a winning edge, are just three examples of how high-tech devices may spread throughout the game in coming years.
In the early 1990s, Rick Greenwald was in Park City, Utah, trying to figure out how to help the United States freestyle aerial ski team prevent head injuries. "They were hitting their heads quite frequently and getting hurt," he recalls. He wanted to determine just how hard they were getting hit, but the impact sensors of the day were too big to be put inside their protective helmets.
By 2000, the technology had changed. He and his partner, Joseph (Trey) Crisco, director of the bioengineering laboratory at Brown University in Providence, R.I., developed the HIT (Head Impact Telemetry) System, based on tiny sensors made by Analog Devices. Six miniature air bags inside a helmet record how often, how hard, and where the helmet has been hit.
Today his company, Simbex Inc. of Lebanon, N.H., partners with sporting-goodsmaker Riddell to offer the safety system (price: about $60,000 for helmets, hardware, and software) to football teams. First used in 2003 by Virginia Tech University, the HIT System has also been employed by North Carolina, Oklahoma, Arizona State, Dartmouth, and Indiana, as well as at several high schools.
While the high-tech helmets can't diagnose a head injury, which must be left to a doctor or trainer, they do send signals to a sideline computer, which keeps track of the number of hits and their severity. The computer also alerts a coach or trainer if the helmet has been struck especially violently.
Head injuries in football, Mr. Greenwald says, are "underreported primarily because you have athletes walking around not wanting to admit they've been hurt, and head injury is not one you can see easily."
Simbex maintains a national database that has recorded some 250,000 head impacts on more than 350 players. By keeping cumulative data on helmet hits, Greenwald hopes to find new insights that someday could lead to modified rules and coaching techniques, as well as better equipment.
Simbex is also engaged in research projects on how the HIT system could be used to study head impacts in other sports, including hockey, children's soccer, boxing, horseback riding, and lacrosse. A contract with the Air Force is testing the system inside the same combat helmet currently used in Iraq.
Another player hazard involves intensive drills conducted during hot weather, which can quietly lead to serious overheating. In one of the most high-profile cases, Korey Stringer, a lineman for the Minnesota Vikings, died in 2001 after a practice when, unbeknownst to coaches and trainers, his core body temperature had reached 108 degrees F.
Today the Vikings, as well as college teams such as the University of Nebraska and the University of South Florida, are experimenting with small body-heat sensors that players swallow like pills. Powered by a hearing-aid-sized battery, the sensors measure body temperature extremely accurately, within a fraction of a degree F. They emit a radio signal that a nearby coach or trainer, using a hand-held receiver, can detect to read the data. The $30 to $40 sensors pass harmlessly through the athlete's digestive system within 24 to 36 hours.
Made by HQ Inc., a Palmetto, Fla., company, the CorTemp monitoring system "gives you an idea of how the core temperature in somebody is rising or if it's pretty steady," says Frederick Mueller, a professor of exercise and sport science at the University of North Carolina and director of the National Center for Catastrophic Sports Injuries. "If it's pretty high, you can take that kid out of practice and cool him down."
And what about high-tech help for coaches? Charles Bower, an astrophysics professor at Indiana University in Bloomington and two partners are trying to interest the National Football League (NFL) in ZEUS, a computer model that advises coaches on what plays to call.
Using data from thousands of real NFL games, ZEUS tells a coach the likelihood of winning the game based on each play he calls. For example, a coach facing a fourth down can see if he is more likely to win the game if he tries for a first down or attempts a field goal or punt at that point. Or, after a touchdown, ZEUS helps him decide between an easy one-point kick or a more difficult two-point conversion. In seconds, ZEUS plays out 100,000 or more simulations of the rest of the game for each choice and tells the coach which decision is statistically more likely to lead to victory.
Mr. Bower and his partners have pitched ZEUS to nearly a dozen NFL teams, but so far none have bitten. That may be because the NFL currently prohibits coaches from using computers on the sidelines.
"They argue they don't want too much technology," Bower says, which seems a bit silly to him since teams already employ a lot of other technology, including radio contact between the coach and quarterback and expensive and elaborate video replay devices.
Bower surmises that coaches may feel reluctant to turn play calling over to a computer. But coaches can always disregard ZEUS's advice, he says. "We said that, basically, this is a tool. It doesn't tell you what you have to do. It doesn't replace the coach. What it does is give you more valuable information."
Bower and his partners are promoting their software program as a tool to prepare for coming games. Employing ZEUS in another way can also help coaches determine the value of each player toward winning games.
Over a 16-game season, Bowers's data shows, following ZEUS would result in adding between 0.7 and 1.25 wins.
"So we tell NFL teams, you're going to be about, on average, one game per season better" with ZEUS, he says. "That's a lot in football: It can mean making the playoffs or missing them, or gaining home-field advantage in the playoffs. That's just a huge value."