Football fans were heartbroken all over England on Wednesday night. The team was beaten by Croatia in the World Cup semifinals in Russia, leading everyone across the nation to accept the fact it’s not coming home— not until 2022, anyway.
Looking back on the memories of the World Cup that wasn’t to be, you might remember seeing a lot of spitting. Not just normal spitting, but players rinsing their mouths out with water and producing a stream of water, rather than drinking it.
England’s captain Harry Kane seemed to do this a lot, squirting water from his bottle into his mouth only for it to come back out again — as did midfielder Dele Alli, and Portugal’s Cristiano Ronaldo.
According to the New York Times, this could be a fitness technique called “carb rinsing.” Drinking a lot of water can lead to bloating, so it makes sense for players to wash their mouths out without swallowing if they are feeling dry. But carb rinsing is where you wash your mouth out deliberately with a carbohydrate solution, which essentially tricks your body into performing better.
It works by receptors in the mouth sensing the carbs and sending signals to the pleasure and reward centers of the brain, saying there is more energy on the way. This makes the muscles work harder, without the negative effects of carbohydrate drinks like stomach heaviness and cramps.
The England team didn’t discuss its nutritional tactics at the World Cup, the NY Times says, but a source familiar with the team’s regimen said carb rinsing was “standard practice.”
A study published in 2017 in the European Journal of Sport Science found that carb rinsing boosted performance in a range of activities. The research team from Coventry University tested 12 healthy men in their 20s, and found after carb rinsing they could jump higher, do more bench presses and squats, sprint faster, and were more alert.
Another study from 2015, published in International Journal of Sport Nutrition and Exercise Metabolism, found that 12 competitive male athletes experienced less fatigue after carb rinsing.
But carb rinsing hasn’t always been found to be successful. In one study from 2017, published in the Journal of Sports Sciences, 15 female runners raced for 60 minutes, once with carb rinsing and once without. The carb solution apparently had no impact on their times. This may be because carb rinsing has more of an impact on quick, immediate activities such as sprinting, rather than endurance events like long distance running.
David Ferguson, an assistant professor of exercise physiology at Michigan State, told the NY Times that rinsing seems to help players feel less fatigued and enhances their attention — something that is very important after more than 90 minutes of play.
Rather than making them run faster or kick harder, “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,” Ferguson said.
When England and Columbia’s match went to penalties, for example, players may have benefitted from a brain boost with 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,” Trent Stellingwerff, a researcher of carb rinsing, told the NY Times. “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.”
It’s not a widespread technique yet, according to Asker Jeukendrup, an exercise physiologist and sports nutritionist at the University of Birmingham, but it definitely seems to be on the rise.
“I hope it’s all deliberate,” he said. “It’s good to see science making its way into real sport.”