What did I do wrong? re: nutrition? - Page 17

07-08-2004, 11:36 AM

That description fits me exactly. If I stop at the top of a tough
climb in Texas summer heat, I feel very faint and come close to
passing out, though I haven't ever collapsed. I found that I need to
keep moving somewhat in order to keep blood circulation up and I can
cool down more slowly.

Terry Morse <[Only registered and activated users can see links. ]> wrote in message news:<[Only registered and activated users can see links. ]>...
> amh wrote:
>
> > I don't usually get dizzy after a ride but I can tell you that I
> > sometimes get dizzy after running. Sometimes it is after a long run or
> > a short run, I can't predict when I'll get this way. A few times it
> > was obviously because I hadn't eaten properly before running. I
> > attribute my dizziness to low blood pressure. I usually do the put the
> > feet above my head if I feel it is necessary. And whatever dizziness
> > passes.
>
> You're describing post-exercise hypotension, a well known (but not
> well studied) symptom. When you stop exercising, the heart rate
> quickly slows down. This reduces the blood flow, and the blood
> pressure drops. Putting your head between your knees should prevent
> fainting. There's an article here that briefly explains what's going
> on:
>
> [Only registered and activated users can see links. ]
>
> (scroll down to "Cardiovascular response following exercise")
>
> I supposed a "warm down" period would reduce the plummet in blood
> pressure, but sometimes that's not possible. On a group ride last
> year, one of the riders got to the top of a long climb and began a
> gentle descent. He passed out, fell and broke his femur. Not good.