Iron Deficiency Without Anemia Impairs Exercise

A report from Cornell shows that lack of iron, even when it doesn't cause anemia, can hinder endurance.

You tire earlier during exercise when your red blood cell count is low because your blood cannot carry as much oxygen as that of a person who is not anemic. However, less than half of the iron in your body is stored in your red blood cells. You also store iron in reserves in your muscles, and other tissues, but you will not become anemic from iron deficiency until you have used up all the iron in your iron reserves.

This study shows that women who lack iron but are not anemic tire earlier, but improve to normal when they are given extra iron. If you feel that you tire early in exercise, get a blood test called ferritin, which measures iron reserves. If it is low, take iron pills to increase your endurance.

Marginal iron deficiency without anemia impairs aerobic adaptation among previously untrained women. American Journal of Clinical Nutrition, 2002, Vol 75, Iss 4, pp 734-742. T Brownlie, V Utermohlen, PS Hinton, C Giordano, JD Haas. Haas JD, Cornell Univ, Div Nutr Sci, Savage Hall, Ithaca,NY 14853 USA

Checked 7/2/12

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