Sport et carence en fer

In recent years, many investigators have observed a decrease in haemoglobin concentration in trained athletes, as well as a high prevalence of iron deficiency, particulary among endurance runners and female athletes. The significance of these modifications remains controversial. Are they an indication of an actual iron deficiency or a physiological response to training or to long-term intense exercise? The existence, now well known in athletes, of a dilutional pseudo-anemia, is a beneficial adaptation that enhances athletic performance, but it may leas wrongly to a diagnosis of iron deficiency. The increase in iron requirements due to intensive prolonged exercise, the increase in iron lost particularly by sweating, and an often inadequate iron supply from dietary intake, especially in female athletes, explain the appearance of an iron deficiency, which, when it is not corrected, leads to anemia. Iron is an essential constituent of haemoglobin, myoglobin and several iron-containing respiratory enzymes; it plays a vital role in energy production. If it is not certain that iron deficiency without anemia can reduce physical work capacity and lead to excess lactate production, it has been shown that even a slight decrease in haemoglobin concentration impairs physical performance by reducing maximal aerobic power. So, regular biological monitoring of these athletes, including, in particular haemoglobin concentration and serum ferritin levels therefore appears to be essential. When iron deficiency is detected, it would seem advisable to give an iron supplement in the aim of avoiding development of anemia and an impairment of performance. An adequate dietary intake would seem to play a very important preventive role with a sufficient animal protein intake and a regular consumption of foods supplying iron. Ar excess of tea and coffee, which reduce intestinal absorption must be avoided and a regular supply of vitamin C, which stimulates this absorption, is recommended.