Giving Blood and Heart Rate

booner said:

Over the past few years, I've noticed that after I give blood my heart rate is elevated 7 - 12
beats for about 4 - 6 weeks. Is this normal?? Am I crazy??

I'm no medical master, but logistically it sounds about right.

An "average" person has about 8 pints of blood in their body. When you give blood, you give up 1
pint which is 12.5%. You now have less blood in your body, but your muscles still need the same
amount delivered to them, so your heart must beat 12.5% more to keep up the blood distribution. If
your resting heart rate is 50bpm, then an elevation of 12.5% will bring it up to 56 bpm. If you are
working at a higher rate like say 130bpm then it will go up by 16bpm.

Over the 4-6 weeks, yor body will regenerate the blood and your HR should start to drop.

Of course I'm just making this [censored] up off the top of my head, so don't take any of this for fact.

booner said:

Over the past few years, I've noticed that after I give blood my heart rate is elevated 7 - 12
beats for about 4 - 6 weeks. Is this normal?? Am I crazy??

I notice an increase in my HR for a few days after a donation but nothing close to your 4-6 weeks.
I'd say that in my case the effect is manifest for at most one week.

Jim Turner

asweepay said:

On Mon, 19 Jan 2004 19:59:10 GMT, "booner" <[email hidden]> wrote: An "average" person has
about 8 pints of blood in their body. When you give blood, you give up 1 pint which is 12.5%. You
now have less blood in your body, but your muscles still need the same amount delivered to them,
so your heart must beat 12.5% more to keep up the blood distribution. If your resting heart rate
is 50bpm, then an elevation of 12.5% will bring it up to 56 bpm. If you are working at a higher
rate like say 130bpm then it will go up by 16bpm.

Over the 4-6 weeks, yor body will regenerate the blood and your HR should start to drop.

Of course I'm just making this [censored] up off the top of my head, so don't take any of this for fact.

Even a blind squirrel finds a nut every now and then. But if I had to take a stab at it I'd say
that the missing blood volume is quickly replaced by water so the number of red blood cells per
unit of volume is diluted. So the heart has to beat faster and push a greater volume to get the
same number of red blood cells per second to the muscles. But then again I don't know any more
about this stuff than you.

JJ

Check out the January issue of Triathlete. "Coaches Corner" has a response to a similar question.
They said that you'll see the effects (through elevated heart rate, just like asweepay said) for ~ 4
weeks...and that you should probably take at least 48 hours off afterwards.

[email hidden] (JimTurner2) wrote in message news:<20040119161305.11022.00003583@mb-
m14.aol.com>...

Quoted message said:

booner said:

Over the past few years, I've noticed that after I give blood my heart rate is elevated 7 - 12
beats for about 4 - 6 weeks. Is this normal?? Am I crazy??

I notice an increase in my HR for a few days after a donation but nothing close to your 4-6 weeks.
I'd say that in my case the effect is manifest for at most one week.

Jim Turner

"booner" <[email hidden]> wrote in message
news:iGWOb.84356$Rc4.305661@attbi_s54...

Quoted message said:

Over the past few years, I've noticed that after I give blood my heart

rate

Quoted message said:

is elevated 7 - 12 beats for about 4 - 6 weeks. Is this normal?? Am I crazy??

This is perfectly normal. You're crazy only if you give blood expecting it to not affect your
performance ability.

Andy Coggan

I guess I didn't expect giving blood to effect my training so much and for so long.

"Andy Coggan" <[email hidden]> wrote in message
"]news:[email hidden]...

Quoted message said:

"booner" <[email hidden]> wrote in message news:iGWOb.84356$Rc4.305661@attbi_s54...

Quoted message said:

Over the past few years, I've noticed that after I give blood my heart

rate

Quoted message said:

is elevated 7 - 12 beats for about 4 - 6 weeks. Is this normal?? Am I crazy??

This is perfectly normal. You're crazy only if you give blood expecting it to not affect your
performance ability.

Andy Coggan