Cycling After Giving Blood

[Psamathe]

No really a question about cycling but about giving blood.

When I was younger I used to give blood, then I travelled to certain countries which meant I was not allowed to give blood and that sort of broke the habit.

So I've decided I must start again. And there is a local'ish session in a few weeks I thought I might cycle to. But then I have memories (or maybe from TV) of people resting with a cup of tea & biscuit after giving and started to wonder if cycling back was sensible. But I thought giving blood was not that big a deal (as far as making you tired afterwards). I'd take my old MTB (somewhat harder work - but I'm not leaving my better bike outside ....).

I'm giving blood whatever, but does it drain you for energy (short-term) ?

Ian

[mjr]

I understand that you still rest after giving and that many people around here ride back without ill effects. Maybe take it easy, carry a bit more snack and drink than you ordinarily would for that ride and be prepared to stop for a rest if you feel at all uncertain?

[LollyKat]

IME yes.

When I was about 20 I donated blood, had the tea and biscuit and then went straight on to play squash with a friend. After a few minutes I didn't exactly collapse but had to sit down on the court and give up the rest of the session.

If your ride back is short and flat you'll probably be OK if you take it gently - but take care!

[Neilo]

I went out for a ride in the evening after giving blood in the afternoon once
I did what I should have done, rest after giving, drink plenty etc.
I went out for my ride because thats what I normally did that evening, didn't occur to me not to.
I'd got about a mile from home, started up the first hill. I felt quite faint.
I stopped, sat on the curb, with my head between my knees for 5 mins or so, then turned round and coasted gently home.
I didn't have a problem until I had to put in some hardish effort.
Thinking about it afterwards, You've got less red blood cells in your body to transport oxygen around, so, you will suffer if you make some high oxygen demand on your body.
That's my experience of cycling after donating, would not do it again.
If you are going to be cycling sedately on the flat, them maybe there would not be a problem.

Neil

[simonineaston]

I'm just reading a book about Lance Gunderson et al, and from the sound of it you (used to? ) get quite used to blood going in and out, if you are (were?) in a top level racing team... although I understand that what went back in wasn't always exactly the same as what went out!

[Mick F]

I've given blood once.
I was feint and very nearly collapsed, and I was over-tired for some hours afterwards.

Cycling?
Not recommended by me at all.

Maybe it affects some folk more than others.

[thirdcrank]

It's a while since I gave blood but I was a regular donor for around 30 years. IME the blood donor part of the National Transfusion Service,or whatever they now call it, is very poorly run. Ive always been convinced that this is the biggest reason for any shortage of donations.

My main reason for posting is to say that you can (or could when I was a donor) donate plasma rather than whole blood. AGFAIK, you can only do this at a permanent donor centre, rather than when a team visits somewhere like the village hall. They connect you up to a machine which collects the blood and then spins it in a centrifuge before returning your donation, minus the plasma. This must have less effect on your system because you can donate plasma more frequently than whole blood.

FWIW, I never knowingly suffered any side effects, but I've sometimes been hacked off by the poor organisation. Had it not been for the fact that the p[eople who may need the blood aren't t responsible for the rubbish system, I'd not have persisted for as long as I did.

[Neilo]

I was feint and very nearly collapsed, .

I fainted once. No breakfast, low blood sugar. Always make sure you've eaten before giving.
When I was an apprentice, we all went to donate. One of the lads fainted when the pricked his finger for the blood test, he wat a bit squeamish. We laughed, oh did we laugh. I know you shouldn't mock the afflicted, but it was funny.

You can also donate platelets, more often than whole blood as well, they do a similar thing to what thirdcrank discribed. one of the guys I used to work with had a record for the number of donations, can't remember how many, but it was in the hundreds.

Neil

[Tigger]

Back from night shifts so just a quick off the top of the head ramble...

There are two aspects to this - physiological and psychological. The chap who passed out after the finger prick (haemoglobin) test is obviously suffering from the latter!

Physiologically, at rest, you have to cope with a sudden reduction in blood volume - say an eight to a tenth depending on your size. (They used to say a pint per stone of weight, I think. The donation is less than a pint now, is it 400 or 450ml?) Anyway, in a fit and healthy person 10% blood loss (making you mildly hypovolaemic) should hardly register on the vital signs (heart rate, respiratory rate, blood pressure, blood oxygen saturation) because your body can compensate without issue up to around 15%. The body has three ways of restoring the volume - short, medium and long term. In the short term in order to maintain balance (homeostasis) it shuts down a bit of peripheral circulation - withdrawing blood from the vascular beds - thus increasing the core volume pretty quickly. Obviously the reason you are encouraged to drink after donating is to bump up the volume a bit but of course this doesn't help with the oxygen carrying capacity.

The other issue, as Neilo has pointed out, is loss of oxygen carrying capability ie haemoglobin (Hb) in the red blood cells (RBCs). Again, in a fit and healthy person, at rest, this should not be a problem.

Now add exercise, and I think it's the hypovolaemia which is the immediate issue more than the loss of oxygen carrying capability. If you start to become warm/ hot/ sweating then your body wants to open up the peripheral circulation and now you are in trouble

As for MickF's reaction - I'm surprised for such a fit and healthy person! So possibly partly psychological (are you squeamish Mick? how do you react to the sight of your own blood?) but maybe also an issue with sudden adjustments to peripheral circulation? Naturally low blood pressure? Do you feel faint if you stand up too quickly? (Do they measure your BP before you donate? I've given up going because of being rejected for low Hb (marginal) and can't recall if they measure BP or not!)

The spleen can restore some of the RBCs but I can't remember the physiology of this (quantity/ immediacy) then your body has to make more RBCs which takes about 120 days - hence the donation frequency - used to be four times a year, now three I think.

I did once upon a time go to hockey training after donating - no problem but I was young then!!!

Edited to correct capillary beds to vascular beds; storage capacitance is held in the venous side of the circulation
Edited to correct LollyKat to Neilo

[thirdcrank]

For some weird reason, a donation of plasma counts as two donations, even though you get the blood back, minus the plasma, so going every eight weeks you can notch up 12 donations a year. IMO the benefit to others is infinitely more important than certificates, badges etc. I'll repeat that IMO, if they got the admin right, there'd be no shortage of donated blood. I did read somewhere after I was no longer able to donate that they's replaced the 0800 number for arranging to attend a session and replaced it with an 0870 number. What sort of buffoon dreams up a trick like that?

[kwackers]

I usually feel dizzy when I first get upright after giving blood, requires me to sit with my head low for a couple of minutes. I have quite happily gone out and done exercise within an hour or so though with no obvious ill effects.

I used to give blood regularly using the mobile vamp wagon but they started changing the dates, didn't say when it would be on site and so I kept missing it and then it just stopped coming altogether...

[ferrit worrier]

we used to have a mobile van come round to work, (got knick named the vampire van) I generally got an early slot but then went back to work after the customary tea and biscuit and at home time I rode home (5 miles), no problem. I think a lot depends on your existing physique and how far you will need to ride.

[Mick F]

As for MickF's reaction - I'm surprised for such a fit and healthy person! So possibly partly psychological (are you squeamish Mick?

Yes.

Do you feel faint if you stand up too quickly?

Often.

Sounds like I've got a double whammy!

[Psamathe]

I did read somewhere after I was no longer able to donate that they's replaced the 0800 number for arranging to attend a session and replaced it with an 0870 number. What sort of buffoon dreams up a trick like that?

It's and 0300 number now - which is free for me. But I really object to these 0844/0844/0870/etc. numbers. I wont deal with any companies that use them, but when forced will only call if I can find the real number (http://www.saynoto0870.com/search.php seems pretty good).

I only had to call because of a particular vaccination I had recently - their web site identified it as an issue but said "Call us to discuss in detail".

Their web site seems OK in terms of finding donation centres/dates. You key in your postcode and it lists where donations are being taken (distances/dates/details). I'm not bothering to "register online" as I don't want e-mails/points/loyalty cards/whatever; don't want online accounts with Facebook shares re-Tweeted to whatever a re-Tweet is. It's just about giving blood to the NHS.

No idea how good the organisation is these days as I've not attended yet (and will be doing everything at the place "on the day"). But web site seems OK (works, you can find the info, etc.).

Ian

[thirdcrank]

If the service has improved recently, that's good to hear: this is one of those times when I have no wish to be right. The ethos behind our donor system - healthy people giving blood etc for the benefit of those who need it - is the best and so much better than paying for donations. It shouldn't be hard to set up a decent system to collect something so important that is given freely.