Good nutrition is important at every stage of training and competition. Both the serious competitive cyclist as well as the recreational cyclist should eat a balanced diet that provides calories adequate to meet energy demands. Athletes consuming less than 2000 calories a day may have difficulty meeting nutrient needs, particularly for iron and calcium. Weight loss, glycogen depletion, and dehydration also are possible results of an inadequate diet. Dietary strategies to enhance or maintain the body's carbohydrate stores are necessary for performance, especially for cyclists with high training miles or participating in road racing and other endurance events. Additionally, cyclists should be encouraged to drink plenty of fluids, especially when in a hot environment. It appears that protein requirements of endurance athletes increase as the duration and intensity of exercise increases. However, factors such as total calorie intake and protein quality should be considered when determining protein needs. Many athletes are concerned about vitamin and mineral intake and often use nutritional supplements both for "insurance" as well as performance reasons. The supplements taken most often include vitamin C, the B-complex, and iron. Vitamins and minerals in excess of the RDA do not improve performance and can be toxic when consumed in large amounts. On the other hand, vegetarians and cyclists with low-calorie intakes may benefit from a multivitamin or mineral supplement.