Giving blood?

oscarbudgie

Does anyone know if giving blood - I donate about once every 4 months - is likely to have any negative effect on performance? I'd always understood that you made the lost blood (a pint - thats very nearly an armful!) up very quickly but reading the latest issue of the magazine sent to donors this doesn't seem to be the case? I'll continue to give regardless of the answer btw.

johndoran

I've been donating for about 35 years now and think that if you take it easy for a few days afterwards it doesnt really effect you. probably if you had a long TT coming up or a long road ride such as a sportive then maybe a week.

Ollieda

We have a guy in our club who gave blood one morning then came straight out on a club run, he fatigued a bit earlier than usual but he said it just felt as if he'd had a really hard ride the day before. I guess it effects different people differently.

Bronzie

oscarbudgie wrote:

I'd always understood that you made the lost blood up very quickly but reading the latest issue of the magazine sent to donors this doesn't seem to be the case?

You make up the blood volume within 24 hours, but this is mostly water. The red cells that actually carry oxygen to the cells (and hence have the greatest affect on aerobic activity) take 4-8 weeks to be fully replenished. So yes, it will definitely affect your performance.

http://www.bikeradar.com/forums/viewtop ... t=12621669
http://www.bikeradar.com/forums/viewtop ... t=12571889
http://www.bikeradar.com/forums/viewtop ... t=12567180
http://www.bikeradar.com/forums/viewtop ... t=12558191

Alex_Simmons/RST

6 weeks or thereabouts to replace lost red blood cells.
Not for someone seeking to train hard or perform at racing.

JAnglesea

It works the other way round too. I regularly give blood but last time I went to donate was 4 days after the Bike Radar 100 mile sportive. It was a tough ride (I only started riding in January) plus I rode to and from the start, adding about 25 miles to the ride. It was and still is the single toughest days riding I've done. (The Long Eaton Reliability a week after starting riding comes close though! )

I never normally have a problem with giving blood and I pass the iron test (I presume this is cheap way of seeing how many red blood cells you have?) easily. This time, however, I (just) failed the simple test and then the more accurate test they do if you fail and wouldn't let me donate. Just shows that a tough ride can really take it out of you.

dave_oc

I used to give blood pretty regularly. I found that for the next week or so I'd definitely notice the difference cycling up hills but this would improve again reasonably soon. However, last year I gave blood regularly, donating as soon as I was allowed to each time (every 3months) and I found that by the end of the year I felt completely drained when cycling and the only reason i could think of was the change in blood donation.

I'm actually a haematologist and discussed this with my transfusion colleagues who felt that it could be that I'd become iron deficient through too frequent donation. I only weight around 60Kg so it could be a possibility. I've since donated just over winter, when i'm training less and not racing, and this has been fine.

For most people, giving blood shouldn't result in a noticeable change in exercise tolerance. However, if you're training hard, racing etc then it may be more significant. Just look at the difference the opposite effect can have when a pro cyclist transfuses pre-race (eg. Vino in the 2008 Tour). The most sensible thing is to base your decision on how you feel post donation. If you feel fine, then its probably not having much of an effect, and so you should carry on giving. The blood transfusion service only survives because people are generous enough to give up their own time to donate, without the expectation of any compensation. The blood is used to support patients undergoing surgery and cancer treatment, during trauma cases and in many other situations, and really is life-saving, so if you are able to give I'd strongly urge you to continue to do so.

Sorry for the sermon! hope this helps!

Edwin

Wasn't it the '07 Tour when vino got done for that?

I give blood a couple of times a year, but not during racing season as it does affect performance. Last month I found I was fine to carry on training, but felt a bit tired for a couple of days. I did joke to one of the staff about taking it home to put in the freezer so I could use it before a race, but they didn't really know what I was on about! :shock:

Bronzie

Just out of interest, has anyone experience of what sort of drop in FTP to expect after donating? Just wondering as I was planning to donate myself tomorrow.

The only info I could find on the Wattage forum was a link to this research paper:
http://www.ncbi.nlm.nih.gov/pubmed/8053038
which seems to indicate a 12% drop in VO2 max 24 hours after donation (but this is for double the normal donation amount if I understand it correctly) returning to normal levels 8-11 weeks later.

Presumably this would lead to a ~12% short-term drop in FTP as well?

dave_oc

Yep, that paper is looking at the feasibility of taking double the normal amount to reduce number of visits etc. It's not great research - they only included 8 subjects so it can't really be applied to day-to-day practice. It suggests an immediate drop in VO2 etc but that this returns to normal by 8-11 weeks after, which is what we expect post-transfusion. The problem with this is always that some people will fall outside this and may take longer to recover.

I think you can be pretty sure that your FTP will drop along with other parameters for a short period post-donation, but for most will recover alongside your blood count after about 8-12 weeks. As long as you're not racing you probably won't notice the difference.

e999sam

I donate several times per year and defiantly feel the difference for several weeks after but as I do not compete seriously any more this does not really bother me.

andy_wrx

Training, I don't really notice that much difference, I'd just take it easier for the 2 or 3 days immediately afterwards.
Racing or doing a big event, I'd schedule the appointment after it rather than just before it.

When I first started donating in my 20's, our manager used to take us to the blood centre and then back via the pub - I'd have one pint and be pi$$ed all afternoon...not sensible

Bronzie

Bronzie wrote:

Just out of interest, has anyone experience of what sort of drop in FTP to expect after donating? Just wondering as I was planning to donate myself tomorrow.

Reckon I've lost 10-15W off my FTP since donating 9 days ago (c. 6%). Not racing again seriously until March so not a problem - I only donate once a year now anyway (off season).