GLOSSARY

Sports Nutrition Guidelines provides general recommendations for nutritional practice in sport. Guidelines need interpretation for the specific athlete and event rather than being copied as an identical prescription for everyone.

Sports nutrition connects food and fluid provision with training, competition, adaptation and health. The appropriate plan depends on the sport, event duration, athlete, environment and available eating opportunities. Adequate energy and nutrient intake form the foundation, while timing and specialized products solve particular problems. A strategy supported in one exercise model is not automatically optimal for every sport. The useful outcome is the athlete's ability to train, recover and perform under the actual conditions.

Energy requirements depend on body size and composition, activity, life stage and physiological circumstances. A maintenance estimate is a starting point for a defined situation rather than a permanent personal calorie ceiling. Training load, recovery, appetite and changes in body mass help evaluate its usefulness. Growth, illness or a change in training schedule may require reassessment. Adequate energy also needs appropriate carbohydrate, protein, fat and micronutrient provision; matching a calorie total alone does not guarantee a balanced sports diet.

Energy availability describes dietary energy remaining after exercise expenditure, expressed relative to fat-free mass over a defined period. It differs from whole-day energy balance and from body-fat percentage. Calculations are sensitive to errors in food records, exercise expenditure and body-composition estimates. No single threshold or short observation establishes a diagnosis for every athlete. Persistent fatigue, impaired recovery or other concerning changes warrant assessment in the broader health and training context rather than a conclusion from one calculated value.

Carbohydrate requirements vary with the intensity, duration and importance of the work. Daily intake relative to body mass describes a different quantity from an intake rate during exercise, which is commonly expressed per hour. A larger daily target does not mean the same amount should be consumed in every session. Match supply to the schedule, starting stores and practical tolerance, and distinguish grams eaten from grams absorbed or oxidized when discussing a fueling plan.

Dietary protein provides amino acids for tissue maintenance and adaptation. Total daily intake, distribution across eating opportunities, protein quality and sufficient energy all matter. A precisely timed drink cannot compensate for an inadequate overall diet, while a convenient food or supplement can help when normal meals are difficult. Resistance training provides the relevant stimulus for muscle development. Interpreting protein as an exercise fuel should not distract from supplying carbohydrate and fat appropriately or from its structural and functional roles.

Periodization adjusts nutrition across sessions, days or training phases to support the work and its goals. Carbohydrate can be concentrated around demanding or important sessions while the broader diet still meets energy and nutrient needs. A lower-demand day can also be a recovery or preparation day, so rest does not imply that food or carbohydrate should be removed. Describe what changes, when and why, and evaluate the quality of subsequent training rather than treating variation itself as beneficial.