Lose another pound.
Credit: Dave Long / Getty Images

In a big road race, the first-place finisher is certain to be a lot skinnier than the last-place finisher. But the winner is also likely to be leaner than the guy right behind him. In races, body-fat percentage predicts performance almost as well as aerobic capacity does. In other words, the leaner you are, the faster you go. As a rule of thumb, you will shed 1 percent in race time for every 1 percent of body weight you lose. That means if you currently weigh 170 pounds and your 10K time is 45 minutes, losing two pounds could lower that by about 30 seconds. Studies have demonstrated that people lose more weight when they weigh themselves often, so as you approach a race it's a good idea to monitor your weight daily and to keep a log. As for what you need to do to shed excess body fat, there's nothing new there: Clean up your diet (eat more fruits and vegetables, cut down on alcohol, and skip dessert), and train more.