Anemia

Sports Anemia

Sports anemia refers to a period in early training when athletes develop low blood hemoglobin for a [Page 49]while, likely reflecting normal adaptation to physical training. Aerobic training increases blood volume, fluid volume, and red blood cell count. While true anemia requires treatment, temporary reduced red blood cell count seen early in training goes away by itself after a while.

Physically active young women, especially those engaging in endurance activities such as distance running, are prone to iron deficiency. Iron status may be affected by exercise in a number of ways. One possibility is that iron is lost in sweat, and although the sweat of trained athletes contains less iron than that of others, it is simply an adaptation to conditioning. Still, athletes sweat more profusely than sedentary people.

In addition, in some athletes at least, physical activity may cause small blood losses through the digestive tract when they take aspirin for sores or to relieve pain.

Low intake of iron-rich foods, combined with iron losses aggravated by physical activity, leads to iron deficiency in physically active individuals. It impairs physical performance because iron is crucial to the body's handling of oxygen. Since one consequence of iron deficiency anemia is impaired oxygen transport, aerobic work capacity is reduced because the person tires very easily.

Sports Hematology

The most common finding in athletes is a dilutional pseudoanemia that is caused by a plasma volume expansion rather than an actual blood loss. Pseudoanemia is not a pathological state and normalizes with training cessation in 3 to 5 days. Pseudoanemia should be distinguished from conditions associated with lowered blood counts. To determine the true anemia state in an athlete, one must take into account not only blood losses secondary to exercise, such as foot strike hemolysis or iron losses through sweat, but losses due to nonathletic causes as well. Depending on the age and sex of the athlete, consideration must be given to evaluation of the gastrointestinal or genitourinary systems for blood loss. Finally, a comprehensive nutritional history must be taken, as athletes, especially women, frequently do not consume adequate dietary iron.

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