‘Sweeep!’ This simple word echoes across curling rinks nation-wide.
And University of Western Ontario professor Tom Jenkyn has discovered there’s a lot more to the perfect sweep than anyone had imagined.
Tom Jenkyn
For the past two years, Jenkyn has played a part in the Canadian Olympic Committee’s Own The Podium Top Secret Fund – a five-year, $8-million sports arms race, so to speak, designed to provide Canadian athletes with an edge in equipment and technique in a variety of sports.
If the curling team makes the podium next month, his work will have played a part in that success.
With backing from the Canadian Curling Association, and the assistance of Olympic-level curling coach Scott Arnold, Jenkyn began research in 2007 into what takes place when curlers sweep in front of a stone on its way down the ice. Sweeping has long been used to fine-tune movement of a stone.
With the use of infrared cameras, he was able to debunk one long-standing myth.
While sweeping will momentarily raise the ice temperature by one or two degrees, it’s not enough to convert ice to water.
“No one is melting anything,” says Jenkyn, associate professor of Human Biomechanics in the Department of Mechanical and Materials Engineering, with a cross-appointment in the School of Kinesiology.
“No one is getting the ice up to the freezing point. Minus two is the highest you’ll ever see the ice temperature get.”
So if ice melting is not assisting the rock into the house, what is? That’s where the biomechanics angle comes in.
Jenkyn says with a turning rock – as it moves down the ice – one side will be moving faster than average. The slower side moves with respect to the pebbled ice surface, creating greater friction between the two surfaces.
“Therefore the slower side has more grab on the ice and tends to curl the rock toward the slower moving side,” says Jenkyn.
“By sweeping, the surface of the ice over which the rock travels is warmed and the friction decreases overall.”
Sweeping also tends to reduce the difference in friction between the faster and slower sides of the rock, therefore the rock curls less and runs straighter.
Working closely with Canada’s Olympic curling team coaches, Jenkyn says the athletes have been “buying into” the research to improve their game. And Jenkyn has found sweeping technique can make the difference between gold and silver.
“It’s all about subtleties,” says Jenkyn, noting positioning of the feet, angle of attack, strength and conditioning and even how one holds the broom can change a shot. “There is a lot that can be gained, even at the elite level, by proper positioning of the broom and the body.”
This curling query also spawned a connected research project for Jenkyn, who recently received $18,640 from the Western Innovation Fund to examine a novel re-design of the curling broom to significantly improve effectiveness.
In collaboration with Mechanical and Materials Engineering professor Jeff Wood, they have optimized the new design for mass production and will bring this product to the Canadian marketplace for the next curling season.
“It’s the kind of broom for the Joe Schmoes in the recreation leagues to help improve their performance,” he says.