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Old July 18th 08, 07:06 AM posted to misc.fitness.aerobic
DrollTroll
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Default aerobic exercise and blood pressure


"joeu2004" wrote in message
...
On Jul 17, 11:16 am, "DrollTroll" wrote:
During the exercise:
Weight lifting *radically* increases bp [...].
And even aerobic workouts raise bp during the exercise.


I stand corrected. Thanks. I am certain that I read over the years
that BP drops during (aerobic) exercise, resulting in light-headedness
in extreme cases. But a google search just now produced some credible
explanations to the contrary that make a lot of sense.
======================================

You really didn't need no (stinkin) studies. It's simple fluid
mechanics/hydraulics.
If your heart is pumping at 2-3 times its resting rate AND at a higher
stroke volume, the pressure MUST go up. As in any pump, any garden hose.

The *real* Q is, Why doesn't bp rise higher than it does, during aerobic
effort?

The answer is two-fold:
vascular dilation, all over the place, AND in fact NEWly opened capillary
pathways that were previously closed.
And probably some reduced blood viscosity, as well-- unless you've got
sickle cell.

And, btw, the bp rise in heavy lifting is so precipitous that there is real
medical concern for older people unwisely feeling their Cheerios with heavy
weights, ESP with a history of fragile vasculature, etc.

Ditto the ICP from passive inversion. The teeter-totter people vehemently
dispute this, but that's because, despite a legitimate product, they still
feel the need to twist logic and science to their advantage.

Blood pressure is an artfully subtle parameter.

==================================



This "cumulative effect" business is dicey.
Short cumulative stuff absolutely *does not* lead to the "aerobic training
effect", which is the synthesis of additional oxidative enzyme pathways.


I agree wholeheartedly (no pun intended). I suspect that some of the
conclusions of recent studies are simply motivated by trying to get
sedentary people to do __any__ kind of phyiscal movement. "Tell
people that they can get some benefits by doing almost nothing many
times a day, and eventually they will get healthy and motivated enough
to do the right thing". At least, that's what I suspect is behind
their thinking.
======================================

Indeed, you'd think Big Media would have at least one altruistic ethical
bone in their greedy li'l bodies, but more likely it's just pandering to the
new "fitness PC-ness".

AND always keeping the consumer off balance with some new tidbit, so the
consumer never knows up from down.

And of course always on the sell. They've got column inches to fill, and
column-inches of ad space to sell, and they're not really particular about
either.

But, having said all that, there is no doubt in my mind that there are
likely a variety of beneficial effects from the cumulative effect theory,
but these effects are most certainly also proportional to intensity.

Altho, having just said that, it is really amazing the benefits yielded by
really middling efforts, such as in the "Conductor Study", where train
conductor's had demonstrably improved markers for health than the much more
sedentary train engineer.
--
DT