Should Athletes Donate Blood?

EndurElite Chief Endurance Officer Matt Mosman discusses how donating blood on a regular basis affects endurance performance.

Video Transcription:

How Donating Blood Affects Endurance Performance

"Blah, blah, blah, blah, bleh. I want to donate blood, but will it make me a slower endurance athlete?" So, I'm gonna apologize ahead of time to all the real-life vampires out there for that terrible, terrible impression. But, in case you didn't get the gist of it, today we're going to talk about what effect donating blood has on your endurance performance. And, we're gonna talk about a study done in 2016, that actually explored this.

The Study On Endurance Athletes Donating Blood

So, what happened is a group of researchers brought together a group of 24 moderately trained subjects, with an average VO2 max of about 55. So, not couch potatoes by any stretch of the imagination. So, they took these 24 people and divided them up into 2 groups. Sixteen were included in the blood donation group, and then eight were in the placebo group. And what they had the subjects do is give a total of three blood donations over the course of nine months, and along the way, they measured things like peak VO2, maximal power output, and certain blood perimeters.

Now, before they had the subjects go in and give blood, they did some baseline measurements on a cycle ergometer to establish peak O2 and maximal power output, and they also drew blood to get baseline blood parameters. So, after all that pretesting was done, the researchers sent the subjects to give their first blood donation. Now, obviously, the group of 16 legitimately gave blood, but how do you fake giving blood in the placebo group, and that's actually pretty interesting. What the researchers did is actually just stick a catheter in the placebo group's arm, blind folded them, and basically told them the purpose of the blind fold was to make sure they weren't going to pass out if they saw the needle going in or the blood flowing out of their arm. So, actually, pretty clever.

So, two days after giving blood, the researchers had the subjects come back into the lab, and again, the researchers tested peak VO2, maximal power output, and certain blood perimeters. And then they repeated this again at one week, two weeks, and four weeks. And, what the researchers found was actually pretty interesting. They found a substantial decrease in peak VO2, maximal power output, and certain blood perimeters at the two days and even up to the four-week time period when they tested where all this basically, significantly decreased endurance performance.

Why Does Donating Blood Decrease Endurance Performance?

Now, why do the researchers think this happened? They think when the blood was drawn, certain blood perimeters were decreased. These being ferritin, hematocrit, blood hemoglobin mass, and red blood cell count. And all these things are responsible for carrying oxygen in the blood to the working muscles. So, with that decrease in blood and those certain variables, less oxygen getting to the muscles, our peak VO2 performance suffers, maximal power output suffers.

So, what's really the take home point of this video? I am all for a good cause. You should absolutely give blood. It all feels pretty good, except for that whole part of, like, jabbing a needle in your arm. But all in all, if you're gonna give blood, I don't think I would do it too frequently. Maybe one time during the year, during the off-season, so it's not going to affect your endurance performance. And interestingly enough, when they tested these over the total of the nine month with the blood donations and the effects on performance, the researchers also found that it minimized long-term adaptations to endurance exercise. So, no bueno there.

But again, back to the point. If you're gonna donate blood, maybe do it once a year, during the off-season, or if you really aren't too concerned about performance and you're past your competitive days, then absolutely donate blood every three months. It's not gonna kill anything if you're not trying to be competitive still, or be in a really high level of performance. So, that is about it for today, my endurance friends.

If you have a friend that donates blood on a regular basis, please share this video with them. If you want other videos like this, head on over to the EndurElite YouTube channel, or the EndurElite blog at Get social with us on Facebook and Instagram. And, until next time, my endurance friends, stay fueled, stay focused, stay fast, and stay informed.