Salt added to beverages during endurance events may be helpful. Iron carries oxygen and is another important mineral for athletes. Female athletes and athletes between 13 and 19 years old may have inadequate supplies of iron. Female athletes who train heavily have a high incidence of amenorrhea and thus conserve iron stores. Iron supplements may be prescribed by a physician if laboratory tests indicate an iron deficiency.
Excess iron can cause constipation.
To avoid this problem, eat fruits, vegetables, whole grain breads and cereals. Calcium is an important nutrient for everyone. Female athletes should have an adequate supply of calcium to avoid calcium loss from bones. Calcium loss may lead to osteoporosis later in life. Dairy products, especially low-fat choices, are the best source of calcium.