Five percent. That’s the improvement in time for athletes who swished their mouths with sucrose compared with those who swished with water, and ran 7.9 mile race. Yes it’s strange, but just swishing our mouths with a rinse that contains a little sugar appears to boost athletic performance. A University of Georgia news release reports that researchers at the school reviewed the times of 16 endurance athletes (nine men, seven women) between the ages of 18 and 45 as they completed a 12.8-kilometer (7.9-mile) time trial on an indoor track, swishing and then spitting out a solution eight times during the run. The athletes completed four time trials using a different mouth rinse each time: a sucrose, or table sugar, solution; a low-intensity sucralose, an artificial sweetener that provides no energy but tastes sweet; a high-intensity sucralose; and water. Here’s what they found:  The endurance athletes who swished-but didn’t ingest-a sucrose solution several times during a time trial significantly improved their running times compared to those who swished with only water. How does it work? The researchers aren’t sure, but they suspect that the sucrose solution, which was sweet-tasting but also provided a small amount of energy, boosts endurance performance by stimulating “reward areas” in the brain related to motor control.