The good, the bad and the questionable. A Herald series looking at modern sports science.
Today: Rugby jersey grip technology
What is it?:
Sixteen years ago the next big thing was a classic sports science one-percenter - an All Blacks rugby jersey with enhanced grip technology to help players catch the ball.
The theory: Boffins at Adidas noticed that when players attempted to catch high kicks they tended to draw the ball into their chests. Every now and then, particularly in wet conditions, the ball would squirt down off the chest. The dropped ball might be harmless in the overall scheme of the match. Or it might just cost a team a world cup final. So what could be done to help the players out?
The science: It all comes down to friction and gravity. If the level of friction created when the rugby ball meets the jersey is increased, gravity's attempt to drag it to earth will be slowed, allowing the rugby player more time to effect the catch, thus saving himself from looking like a complete turkey in front of a global audience of millions.
The experts: Michael Cain, the founder of Loughborough's University's prestigious Sports Tech Institute, has studied grip technology extensively. "What we know for sure is that a wet rugby ball and a wet rugby jersey slides very easily in the absence of a grip technology," says Caine. "If you then put a high quality grip technology [on the jersey] the amount of traction is way more - multi times more - than if you have no grip or a poor grip technology."
Boom. Brilliant idea, then. But not, it seems, always brilliantly executed.
"Some of the early grips were silicone overlays and the absolute irony was that they made the grip better in the dry and worse in the wet," says Caine. "I couldn't believe it when I started testing these shirts. That was quite a revelation."
Things have improved. Modern versions - which are still popular with a bunch of manufacturers - use a lattice structure that is proud of the shirt that interferes with the pimples on a rugby ball, producing a profound amount of traction between the ball and the shirts in wet conditions.
"Basically it works if you understand what you are doing," says Caine. "Under wet conditions will it give you an advantage? Yes it will. Can you quantify that more generally? No you can't.
"Anecdotally those guys that are fielding high balls in the wet love it."
I guess it worked a little bit but when it got wet, it potentially got a bit more slippery.
Adidas pioneered grip technology and the German giant has been one of the first to lead the charge away from what it now admits was a bit of a gimmick. "The feedback from the players and management was that it was not something the All Blacks were looking for," the company's category director for rugby Francois Tabard says. "It was considered more as a gimmick that a performance feature."
It also didn't really work, admits Adidas senior director for team sports Simon Cartwright.
"I guess it worked a little bit but when it got wet, it potentially got a bit more slippery. I don't think it made it particularly worse because ours wasn't a fixed sheen, it was little dots. It wasn't significantly worse but it didn't bring a lot of benefit."
The athletes: So did it work? "Not at Twickenham against France," says a somewhat rueful former All Blacks prop Craig Dowd recalling the shock 1999 semifinal loss to France. "If you want to make a story about it let's say it f***** us up completely and it was completely their fault!
At the end of the day what are we talking about, something that might offer point-zero-zero-zero whatever percent?
"From my perspective it was just 'hey loosen up around the waist - I'm a prop'. They were like oh no it's new technology and it has got to be skin tight and all that sh**'. Kees Meeuws, Carl Hoeft and myself went 'nah, just make them a bit more fitting'.
"We wanted the rubber dots to go down the front of the jerseys for gripping locks and props in scrummaging."
To the players in the '99 squad, the jersey was more about Adidas making a marketing splash than genuinely providing a performance edge.
"At the end of the day what are we talking about, something that might offer point-zero-zero-zero whatever percent?" says Dowd. "It's not going to make you run faster or jump higher. You still sweat and you still bleed and you still do the hard work to get in that jersey. The jersey itself is not going to make you some sort of super hero."