The IAAF has released a comprehensive guide to sports nutrition designed to offer athletes the latest information on fueling their training and performance.
The IAAF Consensus Statement on Nutrition for Athletes, published in the International Journal of Sports Nutrition and Exercise Metabolism, includes a summary of the latest scientific developments relevant to athletes and 16 articles on different facets of sports nutrition.
Key findings from the Consensus Statement:
- The usefulness of high-fat, low-carbohydrate diets is limited to selected individuals, events or scenarios in distance events.
- Low Energy Availability, which can result when athletes consume less fuel than they are using, is a primary cause of RED-S, formerly known as Female Athlete Triad syndrome, in which disordered eating, loss of menstruation and osteoporosis occur, but can also contribute to reduced testosterone levels and libido in men, poor bone health, increased risk of illness and injury, gastrointestinal disturbances, cardiovascular disease, impaired training capacity, and performance.
- Low Energy Availability is known to be a major risk factor in the development of bone stress fractures and should be corrected in both the prevention and treatment of such problems.
- A food-first philosophy is promoted in relation to nutritional needs, and supplements should only be used under supervision to treat or prevent nutrient deficiencies. Only five supplements have an evidence base of contributing to performance: caffeine, creatine, nitrate/beetroot juice, beta-alanine, and bicarbonate. But there is a risk of ingesting banned substances in the use of any supplements.
- Nutrition can help during the rehabilitation of muscular injuries. Goals should include adjustment to new energy requirements and distribution of protein intake to minimize the loss of lean mass and increase muscle repair.
- No direct benefits have been associated with the avoidance of gluten by clinically healthy athletes.
- Vegetarian diets can theoretically support athletic demands, but special attention and good planning are required to ensure adequate intake of energy and specific nutrients that are less abundant or less well absorbed from plant sources (eg. iron).
- Evidence that carbohydrates (CHO) consumed during exercise can provide an additional benefit via the brain and nervous system. CHO can stimulate areas of the brain that control pacing and reward systems via communication with receptors in the mouth and gut. This “mouth sensing” of CHO provides another reason for the frequent intake of CHO during longer events and shorter ones in which it may not be necessary to provide muscle fuel.