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How soon can you race after a blood donation?

blood cells iron anemiaHow soon can I race after a blood donation?

Any runner who also wants to be a good Samaritan, has probably pondered this question. A recent study, published in Transfusion, sought to determine how long it took for runners who gave blood to be able to perform at the same level they had pre-donation.

The study analyzed nineteen men who fit the profile of a regular blood donors–this means they were not anemic. Anemia is a severe iron-deficiency, which can be the result of a poor diet or overtraining (or a combo of both). Anemia is diagnosed through a blood test, which will show low hemoglobin and ferritin levels. Runners that have low iron should not donate blood if they are planning to continue to train (plus, blood agencies don’t want blood that is iron deficient).

The subjects performed a 3K time trial and then made a standard blood donation. They repeated this time trial, three, seven, 14 and 28 days after their original donation. On each trial day, the men had their hemoglobin (a protein in red blood cells that carries oxygen) measured.

By the 14th day after giving blood, the men were as fast as they were prior to the donation, but their hemoglobin levels remained lower than before the donation by 5.9 per cent. On the 28th day after the donation, hemoglobin levels were improved, but still lower than pre-donation. What this shows is that you can race as soon as two weeks after a donation, but that your body isn’t at its optimal potential.

Runners should be advised to avoid giving blood in the months prior to an important race or training module. The best time to donate would be during the off-season when one is not placing the same stress on the circulatory system, or in the week after a race, when one is about to enter a recovery phase.

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