EPO and the placebo effect

So.... wrote:

Rather, the key distinguishing feature was that the responders had a greater increase in erythropoietin concentration with acute altitude exposure, which remained elevated for a more prolonged period of time. Indeed, the erythropoietin increase in the responders after 2 wk at altitude was equivalent to the peak response in the nonresponders, in whom erythropoietin had returned to baseline.

The problem with that study is that it was not double blinded, or placebo controlled, so does nothing to address the placebo effect, and due to design, cannot differentiate cause and effect. It is well known that erythropoietin concentration increases with hard training, so it is not surprising that responders had elevated erythropoietin concentrations after training. If LHTL is as susceptible to the placebo effect as recent studies show, then the hardest trainers would be those most impacted by the placebo, and due to their hard training they would see the biggest improvements in erythropoietin concentrations. Their hard training would also lead to improved performance, so whether erythropoietin concentration increases caused performance improvement is impossible to determine from this study.

EPO may well improve performance in well trained athletes, but there is a lack of high quality studies.

Here is a statistical analysis of Cycling results which is also dubious of the impact of EPO on pro cycling, and multi day cycling events would likely get a much bigger benefit from maintaining high blood values of the period of race than other once-off endurance events, given the fall in blood values in undoped athletes across the course of the event:

Might explain why many cyclists continued with transfusions, despite wide spread EPO availability.

I'll take the word of someone like Bjarne Riis, who took his crit into the 70s (and luckily survived) over the "study" you provided any day of the week. Seriously? Anemic patients at 36? Not relevant, compelling, or comparable. Further, infusion of plasma or saline easily resolves any quibbles about total blood volume. Dopers are so far ahead of researchers, it's not even funny. Not that it's the researcher's fault that they can't perform unethical studies.

Aiden Burley wrote:

Rly = unbrainwashed = troll

Arlo- "see you tomorrow unbrainwashed"

unbrainwashed- "i don't know. the sun my not come up."

Arlo- "well it's risen every day since the dawn of time. I'd say that given the evidence I can reasonably assume that it will rise again tomorrow morning. We've observed that the sun is central to our solar system, the earth rotates around the sun and spins on it's axis. As long as the earth still spins we will see the sun again tomorrow morning. This information has been known to mankind for hundreds of years."

unbrainwashed- "I dunno can you REALLY say with 100% certainty that it will rise high in the sky again? I'm just not sure."

common wrote:

Jesus Christ guys. Come on.

Are you seriously suggesting that the effects of EPO are purely placebo effect? Are you retarded? Honest question. Are you mentally retarded?

You are still avoiding the issue of how oxygen uptake can be increased without extra mitochonria?

Yes EPO dosing can have a placebo effect, just as sugar pills can.

There is no point getting agry. Why don't you just address the real issue of HOW extra red blood cells than we need deliver more oxygen?

You can't or won't answer the question.

common wrote:

Jesus Christ guys. Come on.

Are you seriously suggesting that the effects of EPO are purely placebo effect? Are you retarded? Honest question. Are you mentally retarded?

You are still avoiding the issue of how oxygen uptake can be increased without extra mitochonria?

Yes EPO dosing can have a placebo effect, just as sugar pills can.

There is no point getting agry. Why don't you just address the real issue of HOW extra red blood cells than we need deliver more oxygen?

You can't or won't answer the question.

Aiden Burley wrote:

Rly = unbrainwashed = troll

No, I'm posting under one name on this thread, and I'm not trolling. That fact that you insist I am shows how you are incapable of rational debate.

unbrainwashed wrote:

You are still avoiding the issue of how oxygen uptake can be increased without extra mitochonria?

Yes EPO dosing can have a placebo effect, just as sugar pills can.

There is no point getting agry. Why don't you just address the real issue of HOW extra red blood cells than we need deliver more oxygen?

You can't or won't answer the question.

People have repeatedly answered your question. If you're not going to bother to read the responses, there's no point in talking to you.

No, they haven't answered the question, just restated the dogma that more RBC's = more oxygen delivery. But you can't exceed your VO2max without having more mitochondria as the author of the article states.

If you can't or won't answer the question, then at least acknowledge that fact that you and everyone else is accepting the indoctrination of a pseudoscientific view of aerobic metabolism.

Yes. Similar to the dogma about gravity that keeps getting passed around. Pseudoscientific drivel!

gravity?

The question is where is the bottleneck. If the limiting factor is oxygen delivery during exercise such that under intense exercise not enough oxygen is being delivered for the mitochondria to working effectively then EPO is helpful.

unbrainwashed wrote:

No, they haven't answered the question, just restated the dogma that more RBC's = more oxygen delivery. But you can't exceed your VO2max without having more mitochondria as the author of the article states.

If you can't or won't answer the question, then at least acknowledge that fact that you and everyone else is accepting the indoctrination of a pseudoscientific view of aerobic metabolism.

unbrainwashed wrote:

No, they haven't answered the question, just restated the dogma that more RBC's = more oxygen delivery. But you can't exceed your VO2max without having more mitochondria as the author of the article states.

If you can't or won't answer the question, then at least acknowledge that fact that you and everyone else is accepting the indoctrination of a pseudoscientific view of aerobic metabolism.

How can I make my computer faster without upgrading the processor? I can add more RAM, upgrade the hard drive. You are looking at one factor and ignoring the others.

Better wrote:

The question is where is the bottleneck. If the limiting factor is oxygen delivery during exercise such that under intense exercise not enough oxygen is being delivered for the mitochondria to working effectively then EPO is helpful.

unbrainwashed wrote:

No, they haven't answered the question, just restated the dogma that more RBC's = more oxygen delivery. But you can't exceed your VO2max without having more mitochondria as the author of the article states.

If you can't or won't answer the question, then at least acknowledge that fact that you and everyone else is accepting the indoctrination of a pseudoscientific view of aerobic metabolism.

The limiting factor in oxygen delivery is the rate of enzyme action inside the mitochonria. What is the rate limiting enzyme in aerobic glycolysis? I don't know, but having more red blood cells will not affect that rate.

This basic stuff- how can you not understand? Oxygen delivery = cardiac output x the arterial oxygen content At rest oxygen delivery greater than oxygen requirements. During exercise oxygen requirments increase so oxygen delivery is increased by increasing cardiac output. However if arterial oxygen content is higher to begin with then cardiac output does not have to be increased as much to deliver the same amount of oxygen. In other words, with EPO you can do the same amount of work with a lower heart rate.

unbrainwashed wrote:

The limiting factor in oxygen delivery is the rate of enzyme action inside the mitochonria. What is the rate limiting enzyme in aerobic glycolysis? I don't know, but having more red blood cells will not affect that rate.

That should be "what is the rate limiting enzyme in the TCA cycle" which my google search tells me is possibly citrate synthase.

Aghast wrote:

This basic stuff- how can you not understand?

Oxygen delivery = cardiac output x the arterial oxygen content

At rest oxygen delivery greater than oxygen requirements.

During exercise oxygen requirments increase so oxygen delivery is increased by increasing cardiac output. However if arterial oxygen content is higher to begin with then cardiac output does not have to be increased as much to deliver the same amount of oxygen.

In other words, with EPO you can do the same amount of work with a lower heart rate.

Yes I accept that, but it is irrelevant to the question of how extra oxygen can be delivered with EPO?

You can't exceed your maximum oxygen uptake without using more mitochondria, which is basically impossible if you are already at VO2max.

The limiting factor is delivery NOT the rate at which the mitochondria can reduce oxygen

http://www.ncbi.nlm.nih.gov/pubmed/10647532

Fart

This pretty much ends the thread right here.

Aghast wrote:

The limiting factor is delivery NOT the rate at which the mitochondria can reduce oxygen

http://www.ncbi.nlm.nih.gov/pubmed/10647532