From: Brian Manning Delaney (b-delaney@uchicago.edu)
Date: Fri Nov 06 1998 - 13:40:46 MST
Max M wrote:
> I just wondere where exercise fits into this?
This is a really good, and really complicated, question. Because
of an absurd time crunch I'm currently under, I will break
Internet Image Maintenance Rule #3 ("Don't Self-Cite"), with
regrets, and point you to a recent discussion in
Sci.life-extension on this (Rule #4: Don't call Rule #3 "Image
Maintenance!!!!":):
http://x14.dejanews.com/getdoc.xp?AN=408207211.1&CONTEXT=910378771.677576897&hitnum=13
(As it happens Deja News cut this article right where stuff
unrelated to CR begins, so no need to get Segment #2.)
That article (and others in the thread) relates directly to
aerobic exercise. For bulking-up, there's been little direct
research done. But there's an indirect connection, of course. If
Holloszy's recent finding holds up, it means that keeping your
body in a state of getting less food than it wants is all that
matters in CR. So you could definitely run, but the "getting less
food than it wants" under a bulking-up regimen would be somewhat
different.
But even with aerobic exercise, I still have my doubts. How many
life-long marathoners make it past 90? Very, very few. Their
AVERAGE life span is above the norm, of course, since they're
much less likely to get heart attacks (and slightly less likely
to die of other ailments). I'm going to wait for more research
before training for a marathon, myself.
> If for example I do weight pushing [....]
Anyone got any rats? A little extra cash to buy some rats? We
should be able to run a simple experiment to test this.
Of course, how do you get rats to life weights? Running wheels
they naturally love. But a reward might be required for
resistance exercise. And rewards are usually food, ergo....
This goes on my Important Stuff for Next Medical Library Visit
list. I'll report back what I find (at least several days from
now, if not several weeks...).
> As some of the posting Doug Screcky has made her
> about the Fat vs. Fittnes seem to imply that
> overall death rate seem much more dependant of
> fittnes than of weight.
Ack! How many different places does Doug post this nonsense?
Jeez.
Everything Doug Skrecky has ever posted on CR, or the relation
between weight and mortality has been wrong in virtually every
way it could be.
Sorry if this is harsh. People with incorrect views should be
treated gently, at first. But after the 2nd, then 3rd, then
4th,... time that you correct someone (and LOTS of other people
correct him), and he keeps posting the exact same arguments,
NEVER responding to ANY of the criticism, there is clearly
sufficient evidence that politeness is not going to do the trick.
(And there is evidence to warrant a suspicion of something
devious in the person: supplement-pushing, for example, in the
case of anti-CR arguments.)
Plus, lives are at stake.
Here's a copy (sorry again for spiting Rule #3!) of a response of
mine to iteration 14 or so of Doug's argument. It's from a few
months ago, or maybe decades. I don't know. It's the same every
time, either way.
---------------------------------------------------
Doug Skrecky wrote:
> In humans it has been found that after physical
> fitness is controlled for, that body weight has
> no effect on mortality, thus strongly suggesting
> that caloric intake is NOT a significant
> modulator of human aging. (19)
Doug, try to think a bit more carefully about possibly
confounding variables before you make claims like the above.
A bit of logic may be useful. You're saying:
1) If A then B;
2) B; ==>
3) Conclude (via a "strong suggestion"): A.
This is fallacious. If (2) is A, then you can (3) conclude B,
yes, but not the other way around. Think of some simple examples
if you don't understand; it's pretty obvious once you think about
it.
Filling in the variables for the case at hand: 1) If someone is
doing Calorie Restriction, s/he is thin (it is strongly suggested
-- I think this is where you intend your qualification to go); 2)
We have a group of people who are thin; 3) Therefore they are
doing CR. (And, therefore, since these thin people aren't living
longer than anyone else -- this, by the way, is WRONG -- CR
doesn't retard aging in humans.)
This is not valid. (Also, as to soundness, someone with a very
high set-point could do CR and not be thin at all.)
Perhaps your thinking is rather this: 1) if someone is thin,
they're doing CR; 2) We have a group ....
Here the problem wouldn't be one of logic, but rather of a fatal
lack of facts. It's hard to imagine that this is your problem
here, but in case it is, a few relevant points follow.
Thinness can be caused by FR (mere food restriction), not CR.
Very poor people, for example, are thin because they aren't
eating enough food. Malnutrition decreases longevity. You
wouldn't contest this, right?
A far more important category of people who are thin for reasons
other than the practicing of CR is people who have sub-clinical
illness. There are _millions_ of them, according to most
epidemiologists. To consider just one of the many types of
disease that can go undiagnosed, consider celiac sprue. This is a
disease of the small intestine (the jejunum) the effects of which
are triggered by a protein in wheat (and possibly in other
grains). The disease results in weight loss. It is often not
diagnosed (_far_ more often than not, in many countries) until
years after the disease process itself begins. Then there's
Crohn's disease, colitis, etc. (See Acta Paediatr 1995
Jun;84(6):672-676, for one of many studies dealing with
undiagnosed celiac sprue.)
And here's yet another serious problem. First, to recap: we so
far have two groups of thin people who aren't doing CR: 1) those
with undiagnosed illness, and 2) those who are malnourished
(people doing FR). But there's a third, very, very big group:
people who are naturally thin.
Doug, are you aware that people vary greatly in "set-point"?
"Naturally" thin people in most cases (close to all cases, I'd
guess) aren't doing CR, they're just disposing of Calories
differently from "naturally" fat people. I'm using scare-quotes
because some of this is nurture, not nature.
Let's, then, consider one aspect of nurture in body weight. There
is a huge social force that compels people to eat less: the
notion that being fat is ugly (or uncool, or bad is some other
way). So who are the people who are going to feel compelled to
change their diet because of this social pressure? The naturally
overweight. The naturally thin will just keep stuffing themselves
(and will remain thin). Stuffing oneself is not CR. Clear, yes?
And if the naturally thin are naturally thin because they have a
higher metabolism, then maybe they're aging faster then the
naturally fat would be if the naturally fat controlled their
diets somewhat (if a high metabolism generates more free
radicals, etc., etc.).
So, in point of fact, the epidemiological issues here are far too
complicated even to begin to try to make suggestions about a CR
effect in humans, let alone "strong" suggestions. (And the
logical connections among the variables are complicated, too --
well, actually, they're not complicated, but, in any case, you
appear to have gotten them wrong.)
Is anyone out there taking Doug seriously? I don't have time to
correct all his mistakes. I hope that by pointing out a few,
people will realize that, however nice a guy Doug may be, he
doesn't understand science well enough to be able to support his
claims. I would be horrified if someone stopped doing CR because
of his articles. (And if he is a Chromium salesman, someone
should arrest him.)
Doug, I'm willing to help you. If you want to send your articles
to me before you post them, I'd be happy to discuss them with
you. But you might as well get someone with more experience than
I to proof them for you. As I said before, if you're in
Vancouver, I suggest popping by the office hours of one of the
many researchers in the area. There's no reason to feel shame in
needing the help of others.
And, finally: Doug, you have a lot of energy to put into
anti-aging efforts. It's partly because of this noble aspect of
your character that it's important that you learn more about
science, and about interpreting scientific studies. With more
training or experience, we could take your posts (including those
on your fly studies) seriously, and then you could have a great,
positive influence on the world.
Good luck,
Brian.
---------------------------------------------------
-Brian.
-- Brian Manning Delaney <b-delaney@uchicago.edu> (No need to CC articles to me.)
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