“I would not go that far,” Ian Rollo, the principal scientist for the Gatorade Sports Science Institute in Britain, said with a laugh. “No way do we take credit for any penalty successes at the moment.”
And yet, carb rinsing will do no harm, Rollo and other scientists say. (The joke is that the only possible risk is getting cavities from sugary drinks.) And there might be some benefit to mouth washing, Rollo said, so “why wouldn’t you do it?”
As the World Cup nears its end, a carbohydrate rinse, manufactured by a New York company called Unit Nutrition, has become commercially available. Researchers at Michigan State University are measuring brain activity in college-age students to try to determine how long a potential performance boost from mouth washing lasts and whether Unit Nutrition’s glucose rinse might improve the focus of athletes and other users.
The results are “very preliminary” but suggest the performance boost lasts about 15 minutes. The rinse seems to counteract fatigue and enhances attention to a task, said David Ferguson, an assistant professor of exercise physiology at Michigan State.
For players in the World Cup semifinals, tired after pressure-filled matches played in the heat for nearly a month in Russia after an entire season with their club teams, carb rinsing does not seem likely to “make them run faster or kick the ball harder,” Ferguson said.
Instead, he continued, “it’s simply going to maximize their focus so that they are not succumbing to fatigue, so they can put themselves in the right position to make the right play.”
As England’s match with Colombia moved toward penalty kicks, it was too late to get any carbohydrates into the blood stream but perhaps not too late for a “brain boost” from mouth washing, said Trent Stellingwerff, the director of performance solutions at the Pacific division of the Canadian Sport Institute, who watched the game and has studied carb rinsing.
“You’re going to do every trick in the book to try to maximize cognitive focus after two hours of a pretty intense match,” he said. “Is there science behind it in a soccer model? Not that I’m aware of yet. Is it going to hurt? Absolutely not. If the athletes believe in it and it’s part of their mojo, will that work? You betcha it will.”