Blood test and performance

The Forum for Endurance Athletes

Blood test and performance

Postby charleskline » Wed Feb 09, 2011 9:44 am

I got some blood taken today and I'm wondering how much this is going to effect my performance. I know giving blood can definitely effect this, but I wondered at what quantity of blood removal does this start to happen?
Charles Kline
User avatar
Posts: 9
Joined: Thu Apr 29, 2010 6:15 am
Location: Philadelphia, PA

Re: Blood test and performance

Postby steve-born » Mon Feb 14, 2011 11:52 am

Hello Charles -

I had this on file from Dr. Bill and I think it will help answer your question, while also providing a lot of useful information. Dr. Bill writes:

When giving blood, will it effect performance and how long afterward does it take the body to restore to normal levels? Endurance athletes should NOT give blood before a race. Giving blood will reduce performance if not advanced-planned and factored correctly within one's training protocols.

When donating blood, 500 milliliters of fluid is lost, approximately 70 grams of hemoglobin (equals 220 mg.Iron) and millions of red blood cells. The fluid loss comes back within a few hours, but restoration of the red blood cells takes over 3 weeks. If you are iron-poor, it takes even longer, and is a medical consideration since a few high-mileage ultra-athletes may lean towards iron-poverty during peak training on occasion. A blood donation consists of 500 ml. or a little over 16 fluid ounces. The loss of 70 grams of hemoglobin[220 mg. of iron] takes at least 3 weeks to replace in the healthiest of athletes, but may not fully rebound in some until 6 weeks after the donation. Exercise should be avoided the day blood is donated, while competitive maximal efforts should ideally be avoided for nearly 6 weeks duration.

Christensen & Christensen [1978] measured athletic performances post-blood donations, reporting a decrease in VO2 Max of -10 to -15%. Most of us do not want to give away 10-15% to our competitors; it's like riding with only half the air pressure in your tires, making the day long and slow. Athletes should have their blood hemoglobin and ferritin checked prior to donating blood. It is also suggested to avoid both intense impact or prolonged endurance running 5 days prior to the donation or until 6 weeks post-donation. Noakes [1991] suggests it is safe to donate blood if ferritin levels are above 60 ng/ml and athletes have not run hard for 5 days. He suggests not giving blood if hemoglobin levels are low, i.e. less than 14.5 g/100ml.


*** Christensen, T., Christensen, G., The effects of blood loss on the performance of physical exercise, European Journal of Applied Physiology 1978; 39:17-25

*** Noakes, T.D., THE LORE OF RUNNING, Leisure Press, Champaign, Ill. 1991:695.

--- END ---

I hope this helps!

Sincerely -

Steve Born
Fueling Expert
Event Sponsorship Coordinator
User avatar
Posts: 300
Joined: Mon Mar 08, 2010 11:16 pm

Return to Endurance Forum

Who is online

Users browsing this forum: No registered users and 2 guests