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Couch to 5K
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Running after donating blood (not straight after) - It is damn hard, four days on!

I went to give blood on Friday night for the first time in about ten years. I was foolishly thinking I would be able to do the Park Run on Saturday morning. I was soon put straight by the nurse on that one. She said that whilst she couldn't stop me, I shouldn't be surprised if I collapsed if I tried it. So fair enough I thought I'll have a lie in then :)

Anyhow, due to my packed social calender over the weekend, and needing yesterday to recover from it :) I didn't actually get out for a run until tonight.

And...... I got a bit of a shock. I didn't keel over or anything but I REALLY struggled. I decided to only to do my short run (about 3.8k) it's a nice route and normally takes me 22 mins or so at an easy pace without breaking too much of a sweat, well ok that's a lie I'm normally very sweaty and bright red. :)

It took me over 25 mins tonight and I struggled through every step and had to stop a couple of times. It felt like I had my week 1 lungs back.

So I have learned another few lessons.

1) The old red stuff is quite important :) , it's what takes the oxygen to your muscles. Give an 1/8th of it away and you can expect your running performance to drop by about the same proportion at least until the missing red blood cells have been replaced, it takes 4 to 6 weeks apparently.

2) Being 4 minutes slower at running for a few weeks isn't important unless I have a world record to aim for, which to be honest I think I have left my athletics career a bit late for that.

3) Drinking lager not long after giving blood gets you drunk quicker than normal, not surprising really :)

So now I have a good excuse for being rubbish for the next couple of weeks. I was just wondering if anyone else has experienced this? It was warm tonight so it might have just been a bad run? I am going to give it another go tomorrow to see if was a fluke.

Anyhow happy runnings chaps and chapesses


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Hey, good for you for donating! I am a regular donor and last time I did the c25k programme I ran & donated in the same day (sshhh.... Don't tell the nurse).

I did find it tough but no more than usual. I wasn't dizzy and didn't keel over-(I thought I might) so result!

I thought I would really struggle due to less oxygen rich blood pumping round my body- but perhaps being a regular donor makes a difference?

PS. It's great having a few wines after donating and finding the giggles come much quicker :) lol.


Hey, well done for donating! I'm a regular donor but I haven't donated since starting the C25K programme in June - I was planning to get booked in but then had a crazy moment two weeks ago and got the rook of my ear pierced, so not sure how long before I can donate again! However I will bear in mind what you say - and see how I get on! I do find I can't drive after donating because I feel a bit weak, and definitely enjoy the effects of alcohol quicker then normal!!


Well done for giving blood ~ I used to, but I have been banned due to having 'survived' cancer.

Take it easy for a day or so, and then see how you feel.

The important part is not how fast or far you run, but that you may have just saved someones life. THANK YOU.

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I usually manage to run on the second day after donating, but just do a gentle 5 km - no hill or speed work.


I think point no1 is very important - I used to donate and had to stop because it was whacking me afterwards, but I shouldn't really have been donating at all because I'm below the minimum weight (not by much, but enough I guess). Perhaps if you see how you go next time, it might have been a one off, everyone's different.

Thanks for donating - a couple of close relatives have benefited from the generosity of donors such as yourself - it's a great thing to do.

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Hi Everyone,

Just a quick update... I did the Park Run this morning and just to be all geeky and scientific I used a Garmin 305 training watch and heart monitor to see what was going on during the run, I don't normally bother using it for the Park Run.

Anyhow, I found the run more difficult than normal as per the other day, and my time was about 2 mins off my personal best.

I have just uploaded the data from the watch and the heart rate info makes interesting reading.....

I found a record of a similar run from three weeks ago and the heart rate figures were as follows.

18% Aerobic range.

85% Anaerobic range.

Todays figures..

1% Aerobic range.

8% Anaerobic range.

86% Vo2 Max range.

The VO2 max range I have not encountered before,

I won't pretend I fully understand what this all means but I think it means...

Aerobic range is where your body supplies energy to the muscles directly from oxygen in the blood.

Anaerobic range is where your body metabolises energy from other sources creatiing lactic acid.

Vo2 MAX is where the oxygen carrying capacity or your cardio vascular system has maxed out and you are soon to be exhausted.

So I think that proves that having less red blood cells for a bit does make a difference and my excuse is valid :)

I am wondering now if running at the Vo2 max level will actually improve my fitness, and burn more calories and generally make me slinkier?

As a bit of an experiment I will keep wearing the heart monitor to see what happens in the coming weeks.

Happy running,



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