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Dozens of hockey sticks are piled into a corner and helmets and skates are stored in cubbyholes. But we're not in the Redmen or Martlets' dressing room. In fact, a further look around reveals computer equipment, special sensors and gauges, and infrared cameras perched high on the walls. In this room on the fourth floor of the Currie Gym, where hockey nets jostle for space with tangled cables and electronic measuring instruments, science and the game of hockey have collided.
The room in question is a research lab in the Department of Kinesiology and Physical Education. And the people who work here conduct serious scientific research into the equipment and skills used to play Canada's national winter sport, research that will go a long way to ensuring both the enjoyment and safety of hundreds of thousands of hockey players worldwide. McGill's Ice Hockey Research Group evaluates the mechanical function of hockey skates, sticks and protective equipment like helmets and visors, as well as the skills required to use them to their maximum potential. They use the latest in biomechanics technology to do everything from testing the safety of helmets to evaluating the skating stride and the physics of gliding in order to develop a better hockey skate.
Thanks to a grant from the Natural Sciences and Engineering Research Council of Canada (NSERC) and a partnership with Nike-Bauer Hockey Inc., Professor David Pearsall and his colleagues in the Ice Hockey Research Group have developed a unique opportunity for graduate studies dedicated to the analysis of movement applied to hockey equipment research and to working with sporting goods manufacturers. The lab's work touches on many of modern hockey's hot-button topics, especially those related to safety, including a recent study on the effectiveness of cages and visors.
"Anecdotally, players and coaches would complain about compromised vision when wearing cages," Pearsall said. "Yet no specific studies have been done. So my graduate student Patrick Dowler and I have recently completed a controlled, goal-oriented movement study to address this issue."
The results showed that cages have a significant effect on response time: a delay of about 30 milliseconds (ms) compared to that of people not wearing any facial protection. Visors had less of a negative effect, about a 15-ms delay in response. While 15 to 30 ms may not seem like much, it can have a substantial effect on performance success in the rapid pursuit and chase game of hockey
"I was hoping to show that it was not an issue, because you want people to wear face protectors," Pearsall said. "Now that we've identified the effect, we can propose cage design changes to improve vision without sacrificing protection of the face, eyes and teeth."
With the attention given to what appears to be the growing number of concussions sustained in hockey, helmet safety studies are also a big part of the lab's work. The group does impact testing on helmets and recently completed a longitudinal study on how helmet materials age. In the past, the foam padding inside helmets would become brittle and break down, making it less effective. Even the hard plastic outer shell would degenerate.
"We just finished a five-year shelf-life study," Pearsall said. "Helmets have a CSA (Canadian Standards Association) certification stamp of approval…but the question has been raised as to how long that is valid for.
"This is an important issue for retailers, as they need to know how long their stock is viable for sale, and to consumers, who need to know if the product is still functional over time. We found that current conventional products are stable – shell and foam materials don't degenerate. The only problem is with glues that dry and fragment, allowing padding to fall out of place. Refurbishing helmets with obvious foam loosening is a possible solution."
Part of the answer to the problem of increased concussions, Pearsall said, is to understand not only the physical response of protective equipment, but also to understand how this equipment in turn influences behaviour.
"It's this whole idea of 'risk homeostasis,' – an intrinsic barometer – not too much, not too little. But as soon as we outfit people with something that they perceive as safer, behaviour gets riskier. They found that when cars first got seat belt laws, speeding went up because people felt safer. Some people think athletes' behaviour changed with facemasks and helmets, too – 'Oh, I can do high sticking. It's not an issue because I'm not going to hurt anyone' or 'I can cross check, he's got a helmet on.' "
The greatest advances in hockey equipment have arguably been in stick and skate technology. The one-piece composite sticks, Pearsall said, are about as light as possible. The stick industry is now working to improve their durability. While skate manufacturers have advanced boot material and construction, Pearsall and his colleagues have taken a more ambitious approach – analyzing the actual ergonomics of skating.
"Skates until recently have been really stiff so as to provide ankle stability – essentially immobilizing the foot and ankle – but at the expense of mobility and skating power," Pearsall said. "We're trying to look at freeing up the foot and the whole limb, so that it can work more like running.
"As with many products, skates have evolved through trial and error, but people don't really know why it works. Even the mechanics of sliding on ice – we really don't know the exact physics of what causes gliding," Pearsall said. "I like to say that we are reverse engineering the skate…we have the technology for that now."
For more information on McGill's Ice Hockey Research Group, and to view examples of how they use 3-D motion capture and other technologies to analyze performance and equipment, visit www.icehockeyscience.mcgill.ca.