Coffee after a workout? Absolutely. A recent study found that athletes who washed down some caffeine with a food high in carbs – think a cup coffee with a bagel – after a workout were able to fuel their tired muscles better than those who just ate the carbs. Researchers say a post-workout jolt can help increase your body's uptake of sugar, which is needed to refuel depleted muscles. And the effect is significant: Athletes in the study who combined caffeine with a meal after a workout had 66 percent more glycogen in their muscles four hours after exercising than those who just ate a meal.