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View Full Version : WHY MUSCLES GET TIRED (Or, The Next Drug to Be Abused by CheatingAthletes)


Prisoner at War
February 14th 08, 01:50 AM
Interesting, particularly the concluding thoughts of the article,
which dovetail nicely with Noakes' thesis of a Central Governor
subconsciously directing athletic effort...but whatever *is* this bias
in research studies against weightlifters?? Why the heck do they use
runners and bicyclists all the time???

On a side note in this political season, it's interesting how
conservative newspapers ***NEVER*** break any real news!! Moreover, I
don't think there's a conservative figure in history who's ever stood
up well, through the ages. God probably wanted old people to die
because they get more and more conservative (moronic), no matter how
many vitamin pills they pop!



http://www.nytimes.com/2008/02/12/health/research/12musc.html?em&ex=1203051600&en=627f6a21952d029a&ei=5087%0A

EXCERPTS

In a report published Monday in an early online edition of Proceedings
of the National Academy of Sciences, Dr. Marks says the problem is
calcium flow inside muscle cells. Ordinarily, ebbs and flows of
calcium in cells control muscle contractions. But when muscles grow
tired, the investigators report, tiny channels in them start leaking
calcium, and that weakens contractions. At the same time, the leaked
calcium stimulates an enzyme that eats into muscle fibers,
contributing to the muscle exhaustion.

....

What did make muscles tired?

The new work in mice, Dr. Brooks said, "is exciting and provocative."
It is a finding that came unexpectedly from a very different line of
research. Dr. Marks, a cardiologist, wanted to discover better ways to
treat people with congestive heart failure, a chronic and debilitating
condition that affects an estimated 4.8 million Americans.

Its hallmark is a damaged heart, usually from a heart attack or high
blood pressure. Struggling to pump blood, the heart grows, sometimes
becoming so large that it fills a patient's chest. As the disease
progresses, the lungs fill with fluid. Eventually, with congested
lungs and a heart that can barely pump, patients become so short of
breath that they cannot walk across a room. Half die within five
years.

In his efforts to understand why the heart muscle weakened, Dr. Marks
focused on the molecular events in the heart. He knew the sequence of
events. As the damaged heart tries to deal with the body's demands for
blood, the nervous system floods the heart with the fight or flight
hormones, epinephrine and norepinephrine, that make the heart muscle
cells contract harder.

The intensified contractions, Dr. Marks and his colleagues discovered,
occurred because the hormones caused calcium to be released into the
heart muscle cells' channels.

But eventually the epinephrine and norepinephrine cannot stimulate the
heart enough to meet the demands for blood. The brain responds by
releasing more and more of those fight or flight hormones until it is
releasing them all the time. At that point, the calcium channels in
heart muscle are overstimulated and start to leak.

When they understood the mechanisms, the researchers developed a class
of experimental drugs that block the leaks in calcium channels in the
heart muscle. The drugs were originally created to block cells'
calcium channels, a way of lowering blood pressure.

....

In the meantime, Dr. Marks wondered whether the mechanism he
discovered might apply to skeletal muscle as well as heart muscle.
Skeletal muscle is similar to heart muscle, he noted, and has the same
calcium channel system. And heart failure patients complain that their
muscles are extremely weak.

"If you go to the hospital and ask heart failure patients what is
bothering them, they don't say their heart is weak," Dr. Marks said.
"They say they are weak."

So he and his colleagues looked at making mice exercise to exhaustion,
swimming and then running on a treadmill. The calcium channels in
their skeletal muscles became leaky, the investigators found. And when
they gave the mice their experimental drug, the animals could run 10
to 20 percent longer.

Then, collaborating with David Nieman, an exercise scientist at
Appalachian State University in Boone, N.C., the investigators asked
whether the human skeletal muscles grew tired for the same reason,
calcium leaks.

Highly trained bicyclists rode stationary bikes at intense levels of
exertion for three hours a day three days in a row. For comparison,
other cyclists sat in the room but did not exercise.

Dr. Nieman removed snips of thigh muscle from all the athletes after
the third day and sent them to Columbia, where Dr. Marks's group
analyzed them without knowing which samples were from the exercisers
and which were not.The results, Dr. Marks said, were clear. The
calcium channels in the exercisers leaked. A few days later, the
channels had repaired themselves. The athletes were back to normal.

Of course, even though Dr. Marks wants to develop the drug to help
people with congestive heart failure, hoping to alleviate their
fatigue and improve their heart functions, athletes might also be
tempted to use it if it eventually goes to the market.

....

So the day may come when there is an antifatigue drug.

That idea, "is sort of amazing," said Dr. Steven Liggett, a heart-
failure researcher at the University of Maryland. Yet, Dr. Liggett
said, for athletes "we have to ask whether it would be prudent to be
circumventing this mechanism."

"Maybe this is a protective mechanism," he said. "Maybe fatigue is
saying that you are getting ready to go into a danger zone. So it is
cutting you off. If you could will yourself to run as fast and as long
as you could, some people would run until they keeled over and died."

February 14th 08, 10:41 AM
On Feb 13, 6:50*pm, Prisoner at War > wrote:
> Interesting, particularly the concluding thoughts of the article,
> which dovetail nicely with Noakes' thesis of a Central Governor
> subconsciously directing athletic effort...but whatever *is* this bias
> in research studies against weightlifters?? *Why the heck do they use
> runners and bicyclists all the time???
>
> On a side note in this political season, it's interesting how
> conservative newspapers ***NEVER*** break any real news!! *Moreover, I
> don't think there's a conservative figure in history who's ever stood
> up well, through the ages. *God probably wanted old people to die
> because they get more and more conservative (moronic), no matter how
> many vitamin pills they pop!
>
> http://www.nytimes.com/2008/02/12/health/research/12musc.html?em&ex=1...
>
> EXCERPTS
>
> In a report published Monday in an early online edition of Proceedings
> of the National Academy of Sciences, Dr. Marks says the problem is
> calcium flow inside muscle cells. Ordinarily, ebbs and flows of
> calcium in cells control muscle contractions. But when muscles grow
> tired, the investigators report, tiny channels in them start leaking
> calcium, and that weakens contractions. At the same time, the leaked
> calcium stimulates an enzyme that eats into muscle fibers,
> contributing to the muscle exhaustion.
>
> ...
>
> What did make muscles tired?
>
> The new work in mice, Dr. Brooks said, "is exciting and provocative."
> It is a finding that came unexpectedly from a very different line of
> research. Dr. Marks, a cardiologist, wanted to discover better ways to
> treat people with congestive heart failure, a chronic and debilitating
> condition that affects an estimated 4.8 million Americans.
>
> Its hallmark is a damaged heart, usually from a heart attack or high
> blood pressure. Struggling to pump blood, the heart grows, sometimes
> becoming so large that it fills a patient's chest. As the disease
> progresses, the lungs fill with fluid. Eventually, with congested
> lungs and a heart that can barely pump, patients become so short of
> breath that they cannot walk across a room. Half die within five
> years.
>
> In his efforts to understand why the heart muscle weakened, Dr. Marks
> focused on the molecular events in the heart. He knew the sequence of
> events. As the damaged heart tries to deal with the body's demands for
> blood, the nervous system floods the heart with the fight or flight
> hormones, epinephrine and norepinephrine, that make the heart muscle
> cells contract harder.
>
> The intensified contractions, Dr. Marks and his colleagues discovered,
> occurred because the hormones caused calcium to be released into the
> heart muscle cells' channels.
>
> But eventually the epinephrine and norepinephrine cannot stimulate the
> heart enough to meet the demands for blood. The brain responds by
> releasing more and more of those fight or flight hormones until it is
> releasing them all the time. At that point, the calcium channels in
> heart muscle are overstimulated and start to leak.
>
> When they understood the mechanisms, the researchers developed a class
> of experimental drugs that block the leaks in calcium channels in the
> heart muscle. The drugs were originally created to block cells'
> calcium channels, a way of lowering blood pressure.
>
> ...
>
> In the meantime, Dr. Marks wondered whether the mechanism he
> discovered might apply to skeletal muscle as well as heart muscle.
> Skeletal muscle is similar to heart muscle, he noted, and has the same
> calcium channel system. And heart failure patients complain that their
> muscles are extremely weak.
>
> "If you go to the hospital and ask heart failure patients what is
> bothering them, they don't say their heart is weak," Dr. Marks said.
> "They say they are weak."
>
> So he and his colleagues looked at making mice exercise to exhaustion,
> swimming and then running on a treadmill. The calcium channels in
> their skeletal muscles became leaky, the investigators found. And when
> they gave the mice their experimental drug, the animals could run 10
> to 20 percent longer.
>
> Then, collaborating with David Nieman, an exercise scientist at
> Appalachian State University in Boone, N.C., the investigators asked
> whether the human skeletal muscles grew tired for the same reason,
> calcium leaks.
>
> Highly trained bicyclists rode stationary bikes at intense levels of
> exertion for three hours a day three days in a row. For comparison,
> other cyclists sat in the room but did not exercise.
>
> Dr. Nieman removed snips of thigh muscle from all the athletes after
> the third day and sent them to Columbia, where Dr. Marks's group
> analyzed them without knowing which samples were from the exercisers
> and which were not.The results, Dr. Marks said, were clear. The
> calcium channels in the exercisers leaked. A few days later, the
> channels had repaired themselves. The athletes were back to normal.
>
> Of course, even though Dr. Marks wants to develop the drug to help
> people with congestive heart failure, hoping to alleviate their
> fatigue and improve their heart functions, athletes might also be
> tempted to use it if it eventually goes to the market.
>
> ...
>
> So the day may come when there is an antifatigue drug.
>
> That idea, "is sort of amazing," said Dr. Steven Liggett, a heart-
> failure researcher at the University of Maryland. Yet, Dr. Liggett
> said, for athletes "we have to ask whether it would be prudent to be
> circumventing this mechanism."
>
> "Maybe this is a protective mechanism," he said. "Maybe fatigue is
> saying that you are getting ready to go into a danger zone. So it is
> cutting you off. If you could will yourself to run as fast and as long
> as you could, some people would run until they keeled over and died."

Would any of the currently available calcuim channel blockers, Adalat,
etc., be
useful re: the above?

Dennis

February 14th 08, 11:40 AM
On Feb 13, 8:50*pm, Prisoner at War > wrote:
> Interesting, particularly the concluding thoughts of the article,
> which dovetail nicely with Noakes' thesis of a Central Governor
> subconsciously directing athletic effort...but whatever *is* this bias
> in research studies against weightlifters?? *Why the heck do they use
> runners and bicyclists all the time???
>
> On a side note in this political season, it's interesting how
> conservative newspapers ***NEVER*** break any real news!!

The only reason idiots that own newspapers are even still
with us, is because their much more advanced intellect brethen
invented
ASCII, satellites, fiber optics, digital computers, ebooks, lasers,
CD,
robots, Spandex, Rogaine, and Evelyn Woods for the idiots.

.





*Moreover, I
> don't think there's a conservative figure in history who's ever stood
> up well, through the ages. *God probably wanted old people to die
> because they get more and more conservative (moronic), no matter how
> many vitamin pills they pop!
>
> http://www.nytimes.com/2008/02/12/health/research/12musc.html?em&ex=1...
>
> EXCERPTS
>
> In a report published Monday in an early online edition of Proceedings
> of the National Academy of Sciences, Dr. Marks says the problem is
> calcium flow inside muscle cells. Ordinarily, ebbs and flows of
> calcium in cells control muscle contractions. But when muscles grow
> tired, the investigators report, tiny channels in them start leaking
> calcium, and that weakens contractions. At the same time, the leaked
> calcium stimulates an enzyme that eats into muscle fibers,
> contributing to the muscle exhaustion.
>
> ...
>
> What did make muscles tired?
>
> The new work in mice, Dr. Brooks said, "is exciting and provocative."
> It is a finding that came unexpectedly from a very different line of
> research. Dr. Marks, a cardiologist, wanted to discover better ways to
> treat people with congestive heart failure, a chronic and debilitating
> condition that affects an estimated 4.8 million Americans.
>
> Its hallmark is a damaged heart, usually from a heart attack or high
> blood pressure. Struggling to pump blood, the heart grows, sometimes
> becoming so large that it fills a patient's chest. As the disease
> progresses, the lungs fill with fluid. Eventually, with congested
> lungs and a heart that can barely pump, patients become so short of
> breath that they cannot walk across a room. Half die within five
> years.
>
> In his efforts to understand why the heart muscle weakened, Dr. Marks
> focused on the molecular events in the heart. He knew the sequence of
> events. As the damaged heart tries to deal with the body's demands for
> blood, the nervous system floods the heart with the fight or flight
> hormones, epinephrine and norepinephrine, that make the heart muscle
> cells contract harder.
>
> The intensified contractions, Dr. Marks and his colleagues discovered,
> occurred because the hormones caused calcium to be released into the
> heart muscle cells' channels.
>
> But eventually the epinephrine and norepinephrine cannot stimulate the
> heart enough to meet the demands for blood. The brain responds by
> releasing more and more of those fight or flight hormones until it is
> releasing them all the time. At that point, the calcium channels in
> heart muscle are overstimulated and start to leak.
>
> When they understood the mechanisms, the researchers developed a class
> of experimental drugs that block the leaks in calcium channels in the
> heart muscle. The drugs were originally created to block cells'
> calcium channels, a way of lowering blood pressure.
>
> ...
>
> In the meantime, Dr. Marks wondered whether the mechanism he
> discovered might apply to skeletal muscle as well as heart muscle.
> Skeletal muscle is similar to heart muscle, he noted, and has the same
> calcium channel system. And heart failure patients complain that their
> muscles are extremely weak.
>
> "If you go to the hospital and ask heart failure patients what is
> bothering them, they don't say their heart is weak," Dr. Marks said.
> "They say they are weak."
>
> So he and his colleagues looked at making mice exercise to exhaustion,
> swimming and then running on a treadmill. The calcium channels in
> their skeletal muscles became leaky, the investigators found. And when
> they gave the mice their experimental drug, the animals could run 10
> to 20 percent longer.
>
> Then, collaborating with David Nieman, an exercise scientist at
> Appalachian State University in Boone, N.C., the investigators asked
> whether the human skeletal muscles grew tired for the same reason,
> calcium leaks.
>
> Highly trained bicyclists rode stationary bikes at intense levels of
> exertion for three hours a day three days in a row. For comparison,
> other cyclists sat in the room but did not exercise.
>
> Dr. Nieman removed snips of thigh muscle from all the athletes after
> the third day and sent them to Columbia, where Dr. Marks's group
> analyzed them without knowing which samples were from the exercisers
> and which were not.The results, Dr. Marks said, were clear. The
> calcium channels in the exercisers leaked. A few days later, the
> channels had repaired themselves. The athletes were back to normal.
>
> Of course, even though Dr. Marks wants to develop the drug to help
> people with congestive heart failure, hoping to alleviate their
> fatigue and improve their heart functions, athletes might also be
> tempted to use it if it eventually goes to the market.
>
> ...
>
> So the day may come when there is an antifatigue drug.
>
> That idea, "is sort of amazing," said Dr. Steven Liggett, a heart-
> failure researcher at the University of Maryland. Yet, Dr. Liggett
> said, for athletes "we have to ask whether it would be prudent to be
> circumventing this mechanism."
>
> "Maybe this is a protective mechanism," he said. "Maybe fatigue is
> saying that you are getting ready to go into a danger zone. So it is
> cutting you off. If you could will yourself to run as fast and as long
> as you could, some people would run until they keeled over and died."

February 14th 08, 12:51 PM
On Feb 14, 4:41 am, wrote:
> On Feb 13, 6:50 pm, Prisoner at War > wrote:
>
>
>
> > Interesting, particularly the concluding thoughts of the article,
> > which dovetail nicely with Noakes' thesis of a Central Governor
> > subconsciously directing athletic effort...but whatever *is* this bias
> > in research studies against weightlifters?? Why the heck do they use
> > runners and bicyclists all the time???
>
> > On a side note in this political season, it's interesting how
> > conservative newspapers ***NEVER*** break any real news!! Moreover, I
> > don't think there's a conservative figure in history who's ever stood
> > up well, through the ages. God probably wanted old people to die
> > because they get more and more conservative (moronic), no matter how
> > many vitamin pills they pop!
>
> >http://www.nytimes.com/2008/02/12/health/research/12musc.html?em&ex=1...
>
> > EXCERPTS
>
> > In a report published Monday in an early online edition of Proceedings
> > of the National Academy of Sciences, Dr. Marks says the problem is
> > calcium flow inside muscle cells. Ordinarily, ebbs and flows of
> > calcium in cells control muscle contractions. But when muscles grow
> > tired, the investigators report, tiny channels in them start leaking
> > calcium, and that weakens contractions. At the same time, the leaked
> > calcium stimulates an enzyme that eats into muscle fibers,
> > contributing to the muscle exhaustion.
>
> > ...
>
> > What did make muscles tired?
>
> > The new work in mice, Dr. Brooks said, "is exciting and provocative."
> > It is a finding that came unexpectedly from a very different line of
> > research. Dr. Marks, a cardiologist, wanted to discover better ways to
> > treat people with congestive heart failure, a chronic and debilitating
> > condition that affects an estimated 4.8 million Americans.
>
> > Its hallmark is a damaged heart, usually from a heart attack or high
> > blood pressure. Struggling to pump blood, the heart grows, sometimes
> > becoming so large that it fills a patient's chest. As the disease
> > progresses, the lungs fill with fluid. Eventually, with congested
> > lungs and a heart that can barely pump, patients become so short of
> > breath that they cannot walk across a room. Half die within five
> > years.
>
> > In his efforts to understand why the heart muscle weakened, Dr. Marks
> > focused on the molecular events in the heart. He knew the sequence of
> > events. As the damaged heart tries to deal with the body's demands for
> > blood, the nervous system floods the heart with the fight or flight
> > hormones, epinephrine and norepinephrine, that make the heart muscle
> > cells contract harder.
>
> > The intensified contractions, Dr. Marks and his colleagues discovered,
> > occurred because the hormones caused calcium to be released into the
> > heart muscle cells' channels.
>
> > But eventually the epinephrine and norepinephrine cannot stimulate the
> > heart enough to meet the demands for blood. The brain responds by
> > releasing more and more of those fight or flight hormones until it is
> > releasing them all the time. At that point, the calcium channels in
> > heart muscle are overstimulated and start to leak.
>
> > When they understood the mechanisms, the researchers developed a class
> > of experimental drugs that block the leaks in calcium channels in the
> > heart muscle. The drugs were originally created to block cells'
> > calcium channels, a way of lowering blood pressure.
>
> > ...
>
> > In the meantime, Dr. Marks wondered whether the mechanism he
> > discovered might apply to skeletal muscle as well as heart muscle.
> > Skeletal muscle is similar to heart muscle, he noted, and has the same
> > calcium channel system. And heart failure patients complain that their
> > muscles are extremely weak.
>
> > "If you go to the hospital and ask heart failure patients what is
> > bothering them, they don't say their heart is weak," Dr. Marks said.
> > "They say they are weak."
>
> > So he and his colleagues looked at making mice exercise to exhaustion,
> > swimming and then running on a treadmill. The calcium channels in
> > their skeletal muscles became leaky, the investigators found. And when
> > they gave the mice their experimental drug, the animals could run 10
> > to 20 percent longer.
>
> > Then, collaborating with David Nieman, an exercise scientist at
> > Appalachian State University in Boone, N.C., the investigators asked
> > whether the human skeletal muscles grew tired for the same reason,
> > calcium leaks.
>
> > Highly trained bicyclists rode stationary bikes at intense levels of
> > exertion for three hours a day three days in a row. For comparison,
> > other cyclists sat in the room but did not exercise.
>
> > Dr. Nieman removed snips of thigh muscle from all the athletes after
> > the third day and sent them to Columbia, where Dr. Marks's group
> > analyzed them without knowing which samples were from the exercisers
> > and which were not.The results, Dr. Marks said, were clear. The
> > calcium channels in the exercisers leaked. A few days later, the
> > channels had repaired themselves. The athletes were back to normal.
>
> > Of course, even though Dr. Marks wants to develop the drug to help
> > people with congestive heart failure, hoping to alleviate their
> > fatigue and improve their heart functions, athletes might also be
> > tempted to use it if it eventually goes to the market.
>
> > ...
>
> > So the day may come when there is an antifatigue drug.
>
> > That idea, "is sort of amazing," said Dr. Steven Liggett, a heart-
> > failure researcher at the University of Maryland. Yet, Dr. Liggett
> > said, for athletes "we have to ask whether it would be prudent to be
> > circumventing this mechanism."
>
> > "Maybe this is a protective mechanism," he said. "Maybe fatigue is
> > saying that you are getting ready to go into a danger zone. So it is
> > cutting you off. If you could will yourself to run as fast and as long
> > as you could, some people would run until they keeled over and died."
>
> Would any of the currently available calcuim channel blockers, Adalat,
> etc., be
> useful re: the above?
>
> Dennis

Did you read the article? Did you read this para?

"When they understood the mechanisms, the researchers developed a
class
of experimental drugs that block the leaks in calcium channels in the
heart muscle. The drugs were originally created to block cells'
calcium channels, a way of lowering blood pressure. "

So if the answer to your question is yes than the above para makes no
sense.