Coach,

I know that when you give blood, you need to take it easy for a day or so until your body replenishes the missing plasma & that the Red Cross will only let you donate every 56 days to give your body enough time to replace the red blood cells, which indicates that you are low on red blood cells for days (weeks?) after donating.  My question is how long between donating & doing a race to be at full aerobic capacity?  Is it safe to assume that when low on red blood cells I wouldn't be able to compete at peak levels?

I want to donate but don't want to handicap myself during racing season.


Thanks,
Ken M

Ken,

Nice to see that you are mindful for the health needs of others!

When you give blood, it will amount to 1 pint which is about 10% of your total blood volume. Although this 10% drop will temporarily decrease your oxygen carrying capacity, it is not enough to cause anemia unless hemoglobin numbers are low to begin with. This of course would be an issue for female athletes and a blood test prior to donation would be advised.

Within 48 hours after donating blood, the body will compensate for this loss by replacing the fluid volume but, more importantly for the athlete, it will take anywhere from 7-10 days to synthesize the depleted hemoglobin. Until the hemoglobin is back to normal levels, the cardiovascular system will compensate for this decrease by elevating the heart rate as it tries to deliver oxygen to the cells. You won’t notice much of a difference if you go on an easy to moderate ride but if you push yourself beyond that, you will feel the effects of your goodwill to the blood bank.

Here’s a few things to consider:

1. Give blood on a rest day and ease up on the next few workouts.
2. No skipping breakfast or lunch before giving blood. Eating a good meal and drinking more fluids throughout the day will help avoid fatigue.
3. Although your body will naturally restore the blood loss and its components, eating iron-rich foods will be beneficial. Foods such as lean red meats, tuna, salmon, iron-fortified cereals, dried fruits and beans. Food and drinks rich in vitamin C will also aid in the body’s ability to absorb the iron. Know that caffeine will adversely affect iron’s absorption so provide a time cushion between ingesting the iron-rich food and your cappuccino.
4. Give blood at least 2 weeks before a competition so your performance isn’t compromised.

My best,
Marilyn

Some definitions:

Anemia – This is the most common disorder of the blood seen in a decrease in the normal number of red blood cells (RBCs) or less than the normal quantity of hemoglobin in the blood.

Blood Volume (Whole Blood) - The circulating volume of red blood cells and serum. The blood volume of the average adult is about 10 pints.

Serum – This is the liquid portion of the blood volume composed of water, electrolytes, albumin and important proteins, such as antibodies.

Hemoglobin (protein) – The “heme” molecule has the ability to bind with oxygen. In areas of excess oxygen, as in the lungs, hemoglobin will bind with oxygen and then releases it in a low oxygen environment, ie. demands of exercise.

Red Blood Cells (RBC) - The cells which contain the hemoglobin molecule.

Hematocrit (Hct) – The RBC portion of the blood expressed as a percentage of total blood volume (RBC & Serum). In a normal adult, the hematocrit is 40 to 45% of the total blood volume.

Hemoglobin concentration (Hgb) - The actual weight (grams) of hemoglobin in 100 grams of whole blood. Another way to express the oxygen carrying capacity of a certain amount (pint, cc, ...) of blood. Used interchangeably with Hct. for that purpose. Normally 14 to 15 grams percent.

Ferritin – This is an intracellular protein in that stores and releases iron for RBC production. An integral part of iron transport. Ferritin will be low when anemia is present.