A recent study by scientists at a leading university has refuted the ideas that high-sugar snacks are a form of instant energy. In their findings, the researchers tested long-distance runners on stationary exercise bikes. The study indicated that athletes who had a sugar-free drink before the workout were able to pedal 25% longer than those who had  a sugar-laden drink. The study concluded that 'athletes may be well-advised to abstain from sugar snacks before exercise.