View Full Version : hematocrit levels


arinowner
04-14-2008, 05:54 PM
I may be rehashing things here but I would like to know if hypoxia tents work that well.
According to several prominate articles on the web the average hematocrit level for a top level pro cyclist is 44.5. The normal range for an [B]untrained[B] male is something like 38.5- 48. I say untrained because according my hemotologist a trained athlete would actual have a lower level do due the increased volume of blood plasma (?) Something to the fact that they would be properly hydrated. Makes sence to me knowing that the more de-hydrated you are, the more your hematocrit level goes up.
So someone please explain to me how a pro cyclist can defy known science and have a a high hematocrit level being properly hydrated. Do they all have naturally high hematocrit levels? Or sleep in hypoxia tents?
I am not pointing fingers I just want to know how they do it since my level went from 43 to 32 after a year of solid training. In reality, I know my level hasn't really dropped is just diluted alittle more. But if I could get a level of 43 and be hydrated would that be better? But what happens when I did alittle dehydrated after a race or a day of hard training? Does my level go off the chart and my blood get thick like jello and my heart have a hard time moving it through my body? I don't really know, that's why I am asking in here for some answers. Thanks in advance.

magnolialover
04-14-2008, 07:45 PM
I may be rehashing things here but I would like to know if hypoxia tents work that well.
According to several prominate articles on the web the average hematocrit level for a top level pro cyclist is 44.5. The normal range for an [B]untrained[B] male is something like 38.5- 48. I say untrained because according my hemotologist a trained athlete would actual have a lower level do due the increased volume of blood plasma (?) Something to the fact that they would be properly hydrated. Makes sence to me knowing that the more de-hydrated you are, the more your hematocrit level goes up.
So someone please explain to me how a pro cyclist can defy known science and have a a high hematocrit level being properly hydrated. Do they all have naturally high hematocrit levels? Or sleep in hypoxia tents?
I am not pointing fingers I just want to know how they do it since my level went from 43 to 32 after a year of solid training. In reality, I know my level hasn't really dropped is just diluted alittle more. But if I could get a level of 43 and be hydrated would that be better? But what happens when I did alittle dehydrated after a race or a day of hard training? Does my level go off the chart and my blood get thick like jello and my heart have a hard time moving it through my body? I don't really know, that's why I am asking in here for some answers. Thanks in advance.

First of all, I'm no expert, but I think with a crit level of 32, you're looking at borderline being anemic, if not outright anemic:

Hematocrit measures the volume percentage of red blood cells in whole blood. Normal hematocrit levels range between 40-52% in men and 35-46% in women. Anemia is considered to be moderate when the hematocrit is between 35-40% in men and 30-35% in women and severe when the hematocrit falls below 35% in men and 30% in women.

The above is from: http://www.gmhc.org/health/treatment/factsheets/anemia.html

I don't recall ever hearing anything about crit level being that low from just working out, or even training hard. I believe I have seen stories about grand tour riders who have been that low at the END of a 3 week grand tour, which unless you're a grand tour rider, I don't think you or I have ever exerted ourselves that much over a 3 week period. It does appear that crit can be affected by hydration levels, but should even out after either re-hydrating (when dehydrated) or by de-hydrating after exercise. Again, it does appear that levels should go back to "normal" or whatever normal is after you get back to where you should be as far as hydration levels are considered.

Hypobaric chambers can increase your crit level, because you can "sleep high and train low" when using an altitude tent. I'd hazard to guess that I'm sure you'd get some sort of increase in your endurance levels if you used one, and continued training as normal, but probably not enough to warrant the huge price tag.

arinowner
04-15-2008, 01:01 AM
First of all, I'm no expert, but I think with a crit level of 32, you're looking at borderline being anemic, if not outright anemic:

Hematocrit measures the volume percentage of red blood cells in whole blood. Normal hematocrit levels range between 40-52% in men and 35-46% in women. Anemia is considered to be moderate when the hematocrit is between 35-40% in men and 30-35% in women and severe when the hematocrit falls below 35% in men and 30% in women.

The above is from: http://www.gmhc.org/health/treatment/factsheets/anemia.html

I don't recall ever hearing anything about crit level being that low from just working out, or even training hard. I believe I have seen stories about grand tour riders who have been that low at the END of a 3 week grand tour, which unless you're a grand tour rider, I don't think you or I have ever exerted ourselves that much over a 3 week period. It does appear that crit can be affected by hydration levels, but should even out after either re-hydrating (when dehydrated) or by de-hydrating after exercise. Again, it does appear that levels should go back to "normal" or whatever normal is after you get back to where you should be as far as hydration levels are considered.

Hypobaric chambers can increase your crit level, because you can "sleep high and train low" when using an altitude tent. I'd hazard to guess that I'm sure you'd get some sort of increase in your endurance levels if you used one, and continued training as normal, but probably not enough to warrant the huge price tag.

Please read the article about hemocrit level and tell me what you think,

http://www.cyclingnews.com/fitness/?id=2004/letters02-16

Dwayne Barry
04-15-2008, 01:02 AM
[QUOTE=arinowner]
"I may be rehashing things here but I would like to know if hypoxia tents work that well."

Go to pubmed and search for review articles on this issue. I wouldn't say they work well but that may be that often the altitude stimulus (in terms of simulated altitude levels and time spent there) is not intense enough. There also seems to be a lot of individual variation in the degree to which people adapt.

"According to several prominate articles on the web the average hematocrit level for a top level pro cyclist is 44.5. The normal range for an [B]untrained[B] male is something like 38.5- 48. I say untrained because according my hemotologist a trained athlete would actual have a lower level do due the increased volume of blood plasma (?) Something to the fact that they would be properly hydrated. Makes sence to me knowing that the more de-hydrated you are, the more your hematocrit level goes up."

Correct, one of the first adaptations to endurance training is an expansion of plasma volume, effectively lowering the hematocrit. Probably occurs because if I understand correctly it increases the stroke volume of heart.

"So someone please explain to me how a pro cyclist can defy known science and have a a high hematocrit level being properly hydrated. Do they all have naturally high hematocrit levels? Or sleep in hypoxia tents?"

No, up until recently they were all taking EPO.

"I am not pointing fingers I just want to know how they do it since my level went from 43 to 32 after a year of solid training. In reality, I know my level hasn't really dropped is just diluted alittle more. But if I could get a level of 43 and be hydrated would that be better?"

That seems to me to be an excessive drop. I've seen < 35% considered anemic. You could have an iron deficiency or something else going on.

arinowner
04-15-2008, 01:32 AM
[QUOTE=arinowner]
"I may be rehashing things here but I would like to know if hypoxia tents work that well."

Go to pubmed and search for review articles on this issue. I wouldn't say they work well but that may be that often the altitude stimulus (in terms of simulated altitude levels and time spent there) is not intense enough. There also seems to be a lot of individual variation in the degree to which people adapt.

"According to several prominate articles on the web the average hematocrit level for a top level pro cyclist is 44.5. The normal range for an [B]untrained[B] male is something like 38.5- 48. I say untrained because according my hemotologist a trained athlete would actual have a lower level do due the increased volume of blood plasma (?) Something to the fact that they would be properly hydrated. Makes sence to me knowing that the more de-hydrated you are, the more your hematocrit level goes up."

Correct, one of the first adaptations to endurance training is an expansion of plasma volume, effectively lowering the hematocrit. Probably occurs because if I understand correctly it increases the stroke volume of heart.

"So someone please explain to me how a pro cyclist can defy known science and have a a high hematocrit level being properly hydrated. Do they all have naturally high hematocrit levels? Or sleep in hypoxia tents?"

No, up until recently they were all taking EPO.

"I am not pointing fingers I just want to know how they do it since my level went from 43 to 32 after a year of solid training. In reality, I know my level hasn't really dropped is just diluted alittle more. But if I could get a level of 43 and be hydrated would that be better?"

That seems to me to be an excessive drop. I've seen < 35% considered anemic. You could have an iron deficiency or something else going on.

I thought the same thing about being anemic however my doctor doesn't seem concerned.
My diet is pretty well watched by a nutritionalist so I don't think my intake of vitamins and minerals is the problem. I had a CBC done showing iron levels were in good shape as well as the size of and proportion of new to old RBC was within normal levels.
Is it possible to by overhydrated?
Doctors have been known to be wrong, he just doesn't seem to to worried about my hematocrit level.

mprevost
04-15-2008, 01:52 AM
[QUOTE=Dwayne Barry]

I thought the same thing about being anemic however my doctor doesn't seem concerned.
My diet is pretty well watched by a nutritionalist so I don't think my intake of vitamins and minerals is the problem. I had a CBC done showing iron levels were in good shape as well as the size of and proportion of new to old RBC was within normal levels.
Is it possible to by overhydrated?
Doctors have been known to be wrong, he just doesn't seem to to worried about my hematocrit level.

If you are unsure, ask your doctor, not a bunch of folks on an internet forum. That said, it pays to be an informed health care consumer. Do your own research (web MD dot com), but this is not the place to do medical research.

Mike

Andrea138
04-15-2008, 04:48 AM
Along with training, being well-acclimated to exercise in the heat can make your plasma volume greater as well (lowering the hematocrit).

If you can afford a hypobaric chamber, go for it.

Kerry Irons
04-15-2008, 04:56 PM
I thought the same thing about being anemic however my doctor doesn't seem concerned. My diet is pretty well watched by a nutritionalist so I don't think my intake of vitamins and minerals is the problem. I had a CBC done showing iron levels were in good shape as well as the size of and proportion of new to old RBC was within normal levels. Is it possible to by overhydrated? Doctors have been known to be wrong, he just doesn't seem to to worried about my hematocrit level.

It is quite surprising that an Hct of 32 didn't trigger alarm bells. What was your hemoglobin (Hb) level? How about ferritin level? If your Hct is below 38, you can't donate blood, and 32 is way below that. It's hard to see where just plasma dilution would push things that low, because that would mean a 35% increase in blood volume, which seems extreme. Even with a good diet, you may not be getting enough iron absorbtion, so you need to look at things like ferritin levels to know whether you've got adequate iron stores.

Redbird
04-15-2008, 05:32 PM
Some facts seemed to be getting a little out of whack here. Over time a well trained endurance athlete will experience an increase in hematocrit. While it is true that sometimes an increase in plasma volume will occur, in steady state, an increase in blood volume will occur and most of the increase will be new red cells. Thus, the hematocrit tends to rise in heavy aerobic activities. The increase in stroke volume of the heart is as much of an effect of the reduced heart rate at comparable levels of activity with an increased cardiac output.
Extensive overtraining or activities that damage blood vessels may result in a reduced hematocrit. The findings of blood in the urine or feces after intense effort is an example of this.
No matter what the cause a hematocrit of 32 should be a source of concern to an athlete and a complete workup should be undertaken to determine the cause. The effect on performance should be profound and noticable at this low level. A sustained hematocrit of 32, overtime and attributed to over hydration, could only occur in an extrememly compulsive water drinker or an individual with some type of renal failure.. If you indeed have a "hematologist" who thinks a hematocrit of 32 is very normal for you, run (or ride your bike), don't walk, to get a second opinion form an unrelated cardiologist or hematologist.

arinowner
04-15-2008, 07:01 PM
Some facts seemed to be getting a little out of whack here. Over time a well trained endurance athlete will experience an increase in hematocrit. While it is true that sometimes an increase in plasma volume will occur, in steady state, an increase in blood volume will occur and most of the increase will be new red cells. Thus, the hematocrit tends to rise in heavy aerobic activities. The increase in stroke volume of the heart is as much of an effect of the reduced heart rate at comparable levels of activity with an increased cardiac output.
Extensive overtraining or activities that damage blood vessels may result in a reduced hematocrit. The findings of blood in the urine or feces after intense effort is an example of this.
No matter what the cause a hematocrit of 32 should be a source of concern to an athlete and a complete workup should be undertaken to determine the cause. The effect on performance should be profound and noticable at this low level. A sustained hematocrit of 32, overtime and attributed to over hydration, could only occur in an extrememly compulsive water drinker or an individual with some type of renal failure.. If you indeed have a "hematologist" who thinks a hematocrit of 32 is very normal for you, run (or ride your bike), don't walk, to get a second opinion form an unrelated cardiologist or hematologist.

I posted a link to a velonews article and I don't think many people read it. It stated that hematocrit levels will fall in a trained athlete. I think there were several references at the bottom of the page where these facts were drawn from.
I didn't come in here with the intension of asking people if I was anemic. I simply wanted to know what other people's levels were and how can the average pro cyclist's hematocrit levels be so high. Not wanting to point fingers about possible EPO use. I am aware of the wide spread use of hypoxia tents in the pro ranks and wondered if they work that well. BTW, why are they illegal in Italy?
I did seek a second opinion. From a certified homeopathic doctor who agrees with me that a level of 32 is low for a male my age (49). We are working on some things right now. He is stopped practicing conventional medicine when his wife died from cancer several years ago. He was/ is an internalist MD
My hemoglobin levels were on par with my hematocrit levels. I understand now that they go hand in hand.
I did notice a drop in performance mainly while climbing.
I did have the feces test done. Grossest test I ever did, and it was fine. No blood in my stool. I even had my liver enzymes checked. There were great! Serum ferritin levels were on the low side of normal but within range.
As far as hydration, I make it a point to drink at least half my body weight in ounces a day. About 85. I don't drink cokes or teas. Only water or pure fruit juices and "always" eat some kind of high vitamin C foods with my iron rich foods. I rarely drink liquids with my meals either. I was told that it might interfer with digestion because it dilutes the acid in the stomach and if I do drink with my meals , it a warm drink instead of something iced. The Chinese never drink cold drinks with meals, Might be something to that.?
I hope that the homeopathic doctor can straighten things out quick. My insurance doesn't cover his office visits.
Any thoughts on homeopathic doctors?

Dwayne Barry
04-15-2008, 10:08 PM
The increase in stroke volume of the heart is as much of an effect of the reduced heart rate at comparable levels of activity with an increased cardiac output.


I don't claim a deep understanding of cardiac physiology but that statement doesn't make sense to me. Why does the stroke volume increase BECAUSE the HR has lowered? My understanding is that since oxygen demands are essentially the same at rest (or at a given work load) after you start training as before you trained, but now that your heart pumps more blood per stroke after training, it simply has to beat less times to achieve the same cardiac output. IOW, cardiac output = stroke volume x heart rate.

The increase in stroke volume within weeks if not days of starting endurance training is largely a consequence of expanded blood plasma volume affecting stroke volume by increasing the preload due to the Frank-Starling mechanism, no?

Consequently, HR lowers at rest or given submaximal workloads because stroke volume increases with training.

lookrider
04-16-2008, 01:21 AM
I was 44 about 5 years ago and 42 about 2 years ago. I'm 43 years old.. I honestly don't think it means much, if it's within a normal range. At 32, I'm surprised you're not fainting.

iliveonnitro
04-16-2008, 06:26 AM
I don't claim a deep understanding of cardiac physiology but that statement doesn't make sense to me. Why does the stroke volume increase BECAUSE the HR has lowered? My understanding is that since oxygen demands are essentially the same at rest (or at a given work load) after you start training as before you trained, but now that your heart pumps more blood per stroke after training, it simply has to beat less times to achieve the same cardiac output. IOW, cardiac output = stroke volume x heart rate.

The increase in stroke volume within weeks if not days of starting endurance training is largely a consequence of expanded blood plasma volume affecting stroke volume by increasing the preload due to the Frank-Starling mechanism, no?

Consequently, HR lowers at rest or given submaximal workloads because stroke volume increases with training.

I think he meant the other way around. Increase SV = decreased HR, which is what you said.

Redbird
04-16-2008, 03:50 PM
There are two types of increased workload on the heart. 1) a pressure load wherein the heart must pump against a higher pressure, and 2) a volume load wherein the heart pumps a larger volume . For various and complicated reasons, the heart is much more efficient in pumping a volume load rather than a pressure load. As training of the heart ensues, the resting heart rate is reduced because of various and complicated neural changes in control of the heart and thus, the stroke volume increases. In highly trained athletes, most of the increase in cardiac output upon exertion is due to an increase in rate. In un trained persons the increase in cardiac output is due to both an increase in rate and in stroke volume. But, because in trained subjects, there is little room of increase in stroke volume, almost the total increase is due to rate increase. This effect can be see well in well trained athletes who take beta blockers which reduce the ability to increase rate. Their performance is greatly impaired because the beta blockers reduce the ability to increase rate and they, unlike untrained individuals have little reserve is stroke volume. In the early studies on beta blockers on trained athletes, it was impossible to do double blind studies because the athelete could sense in the first hundred yards whether he was on beta blockers or placebo because of the effect on his performance. I remains my contention that blood volume increases in trained athletes and much of that increase in due to new cells due to aerobic training. It is this increase in cells which alllows blood doping to be effective. Some acheive the higher red cell content by training, others by altitude, and , of course, other by illegal means such as transfusion or EP.
To say that a trained athlete with a higher hematocrit is using an altitude tent or EP is not valid without tests results. This is why the normal upper level for accepted hematocrit is 50
Additionally, an increase in preload will not, in and of itself, produce either an increase in cardiac output or stroke volume in the prolonged steady state. The body autoregulates its own oxygen delivery. Should an increase in preload occasion an increase in cardiac outpup , and oxygen delivery, above that needed by the body, the arterioles will constrict to reduce cardiac output, the arterial pressure will rise and an increase in urine output will return the preload to normal values in the steady state.

Kerry Irons
04-16-2008, 04:58 PM
I did seek a second opinion. From a certified homeopathic doctor who agrees with me that a level of 32 is low for a male my age (49). We are working on some things right now.

Any thoughts on homeopathic doctors?

Yes. There is no scientific support whatsoever for homeopathy. It is junk science in the worst way. Go to any reputable medical web site, and read up on it. It's a scam, a hoax, and defies all logic. Double blind studies prove that it doesn't work any better than placebo, and how could it? It's just water. Homeopathy claims that the water has memory, which is a TOTALLY disproven hypothesis. Don't waste your time or money.

magnolialover
04-16-2008, 05:06 PM
Yes. There is no scientific support whatsoever for homeopathy. It is junk science in the worst way. Go to any reputable medical web site, and read up on it. It's a scam, a hoax, and defies all logic. Double blind studies prove that it doesn't work any better than placebo, and how could it? It's just water. Homeopathy claims that the water has memory, which is a TOTALLY disproven hypothesis. Don't waste your time or money.

Got to roll with you on this one Kerry for sure.

The only thing a homeopathic doctor is going to do for you is to keep you sick.

Dwayne Barry
04-17-2008, 04:25 AM
As training of the heart ensues, the resting heart rate is reduced because of various and complicated neural changes in control of the heart and thus, the stroke volume increases.

Well I'm still not following you. Why does the stroke volume increase BECAUSE the HR decreases? Is there an increased injection fraction because of increased contractility of the heart? Greater preload because of more time for filling of the left ventricle at a lower HR?

There definitely are changes in neural and hormonal responses of the CV system following endurance training but the explanation which is almost always given for decreased HR at a given workload, including rest, is increased blood volume leading to a greater preload. Out of curiosity I looked it up in ACSM's Advanced Exercise Physiology and the information they provide indicates that increased stroke volume (due to blood volume expansion with endurance training) leads to reduced HR, not the other way around.

Dwayne Barry
04-17-2008, 05:43 AM
Yes. There is no scientific support whatsoever for homeopathy. It is junk science in the worst way. Go to any reputable medical web site, and read up on it.


http://www.quackwatch.com/01QuackeryRelatedTopics/homeo.html

Of course, we're just ignorant and not sufficiently open-minded.

stumbler
04-17-2008, 08:29 AM
Well I'm still not following you. Why does the stroke volume increase BECAUSE the HR decreases?

I agree with iliveonitro - I think it's the other way around:

1. Training happens
2. as a result, stroke volume increases (muscles get bigger/stronger)
3. therefore HR decreases