Functional food for exercise performance: fact or foe?

To present food components showing evidence for improved sport performance in the light of the scientific literature from the past 2 years.

Appropriate nutrition is essential for sport performance. Nutritional products containing carbohydrates, proteins, vitamins, and minerals have been widely used by athletes to provide something extra to the daily allowance. Currently, the field of interest is shifting from macronutrients and fluids to physiologically active isolated food components. Several of them have been demonstrated to improve sport performance at a higher level than expected with a well balanced diet. In the present review, we will focus on the benefits of creatine, caffeine, branched-chain amino acids, and more particularly leucine, beta-alanine, bicarbonate, and glycerol ingestion on exercise performance.

A bulk of products are sold on the market labeled with various performance benefit statements without any scientific evidence. These food components are often used without a full understanding or evaluation of the potential benefits and risks associated with their use. There is thus a real need to classify food components on the basis of their evidence-based effectiveness.