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question about physiology

Thread Status: Hello , There was no answer in this thread for more than 60 days.
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New Member
Sep 12, 2003
I just had some blood work done, and the RBC was 4.67 (on the low side of the scale 4.1-5.6 (some internet sites list a higher scale)) and hemoglobin was 13.7 (scale 12.5-17). I thought the counts should be higher, considering all the training (static tables, underwater hockey, plenty of diving). So, I had a bunch of questions, and any answers would be much appreciated.

Isn't freediving training supposed to produce high hemoglobin in the blood? I have only been training in earnest for about four months. How quickly/slowly do the hemoglobin counts change? Is it possible that four months is just not long enough to see any significant increases?

Is there a chance I have been overtraining, resulting in lower than normal counts? Do the hemoglobin counts change from day to day, so that perhaps it was just a bad day?

How long could I expect it to take to improve my hemoglobin counts? I have been eating smoked clams (which on the box purport to contain 100% RDA of iron), and soy protein shakes. I browsed the internet, and found all kinds of information about diet to improve iron that started to sound like voodoo science. I mean, couple years ago I was trekking in Nepal, and the sherpas there (who I am told have hemoglobin counts off the charts), were unbelievably fit. I was in top shape, but at around 4,500m I was seriously dragging. These sherpaswould fly by me carrying four, five times as much gear. And, this is the amazing part, all they eat is dol bat, I don't know if I spelled that right but it's just rice and beans. This makes me wonder how much a role diet really plays.

Some of these internet sites made some crazy claims, like over-hydradation lowers RBC (never heard that you could drink too much water), coffee and tea can reduce iron absorbtion by 50%, and soy protein can inhibit iron absorbtion. Seems like you have to plan your diet like the national budget to stave off anemia, but I keep thinking of those sherpas. Dol bat! That's all they eat.

Once again, any suggestions or leads on good sources of information would be much appreciated.

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Hi Michael

My hemaglobin level is also on the low side of average, based on the simple test that they do when you give blood. Don't know why, but it is consistant.

If you are a vegetarian, and you don't take iron supplements, then you are almost certainly iron deficient. Last year I bought myself a blood analyzer, and despite years of apnea training, cardio, etc..., my hemoglobin was 13.5 g/dl, borderline anemia.

Soy blocks absorption of iron and almost every mineral, especially zinc.

The fastest way to get iron into your system is to eat red meat with iron supplements at the same time. If you are iron deficient it will take a long time to refill your iron store.

Hydration has a dramatic effect on your results (perhaps up to 1.0 g/dl), but even so you'd still be on the low end.

I could go on for ages about this topic.

Doing exhale statics is a good way to measure your blood quality, if you don't have your own blood analyzer.

Eric Fattah
BC, Canada

You bring up something that I was just wondering about today!:D

Is a vegetarian diet better, or worse, for apnea training as compared to a diet that includes meat?

Michael, you should adjust your diet in terms of effective iron absorption since vegetarian diets are poorer than the omnivorous counterparts when we analyse part of their micronutrient effectivity.

This article will clarify general issues:


Now, when we consume phytic acid in cereal-based and legume-based complementary foods (like soybeans, soy proteins, etc.) iron and other essential minerals (Ca, Zn, Mg...) are not well absorbed, I mean phytates bind to these minerals in the digestive tract and prvent them form being absorbed in the diffusion process that occurs during absorption.

So, what to do? Easy, consume cereal and legume based products (including soy and derived products) that have been fermented, i.e. miso and soy sauce; or if processed and cooked products are consumed (which is a common practice in today's society) by adding to your diet compunds such as ascorbic acid (vit. C) or commercial sodium EDTA to avoid that acid binding to the essential minerals.

More info is contained in this article, which does not directly discuss the nutrient soy but it is applicable anyway. OTH, forget about the sponsorship involved in this research. This stuff has already been proved in dozens of other food science articles:


Good luck with your nutritional choice, gerard.
Thank you for the replies and information. I have a follow up question:

Have any of you who may have started with blood counts in the low end of the range experienced significant (and documented) improvements as a result of dietary changes (more red meat)? It would be interesting to have first hand accounts of people who signficantly increased blood counts by just eating different foods.

I read somewhere on the net about athletic anemia, which sets in during the initial phases of heavy training but tends to normalize when the body has a chance to catch up to the stress of training. This make some sense, but I don't understand how exercise and training would reduce the amount of iron in the system (except perhaps for boxers who bleed all over the place).

Efattah, how much was the blood analyzer?

Once again, thanks for the reponses.

Exercise stress can deplete iron through the release of myoglobin ("exercise myoglobinemia"). Sometimes the condition can result in serious physical complications and in rare cases it can result in death.

If you are suffering from exercise myoglobinemia, the urine tends to pick up a characteristic dark tone (described as coffee or maple-syrup color). There is a ton of literature on the topic on the internet -- just do a google search using "exercise myoglobinemia" as the key phrase.
When I got my blood analyzer I was at 13.5g/dl. After changing my diet/supplements now I'm at 16.5g/dl.

My blood analyzer is a Hemocue B-Hemoglobin analyzer. I bought one new for CDN$900 and then I bought one off ebay for (?) USD$350 or so. The one off of ebay worked, but it needed accesories which I had to use from the brand new one.

Eric Fattah
BC, Canada
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