CYCLING PERFORMANCE TIPS

Anemia

• blood volume - The circulating volume of red blood cells and serum. The blood volume of the average adult is about 10 pints.
• serum - The liquid portion of the blood volume. Serum is composed of water, electrolytes, albumin, and other important proteins (such as antibodies).
• hemoglobin (the protein) - A molecule which can bind oxygen. In areas of excess oxygen (i.e. in the lungs) hemoglobin will take up (bind) oxygen. When there is a low oxygen environment (i.e. at the cell level, particularly cells involved in exercise), hemoglobin releases bound oxygen.
• red blood cells (rbc) - The cells which contain the hemoglobin molecule.
• whole blood - What is following through you circulatory system - red blood cells and serum. 10 pints in the average adult.
• hematocrit (hct) - An expression of the percent of whole blood that is red blood cells. In a normal adult the hematocrit is 40 to 45% of the total blood volume, thus the normal hematocrit is 40 - 45%.
• hemoglobin concentration (hgb) - The actual amount (weight) of hemoglobin (in gms) present in 100 grams of whole blood. It is just another way to think of the oxygen carrying capacity of a certain amount (pint, cc, etc.) of blood and is often used instead of hct. for that purpose. Normally 14 to 15 grams percent.
• ferritin - an iron transport protein in the serum that supplies iron for red blood cell production. In anemias resulting from low total body iron stores (the raw materials for blood production are in short supply), the ferritin will be low.

ACQUIRED ANEMIA IN THE ATHLETE

• Dilutional or pseudoanemia (sports anemia)
• Exertional hemolysis
• Iron deficiency anemia

A) Dilutional Anemia

The cause is thought to be related to the fact that with each workout you become slightly dehydrated (total blood volume decreases below normal - now 9.5 pints instead of the "normal" 10), the body senses this deficiency in the kidney (the renin/angiotensin system kicks in) and in the pituitary ( there is an increase in ADH hormone release from the pituitary). This results in fluid retention of a slight degree when you are able to drink adequately and replete your exercise fluid losses.

The degree of dilutional anemia correlates with the intensity of exercise and is usually in the range of 5 - 20% below your normal hgb, not a 20% drop in your absolute hgb or hct. With moderate exercise, the hgb may decrease 0.5 gms, and in elite athletes the hgb may be as much as 1 gram lower than their "normal" range. Dilutional anemia can be seen within a few days of starting or intensifying exercise, and will correct itself back to normal within a few weeks of stopping exercise. It should be suspected if the ferritin is normal in the face of newly noted anemia, and can be confirmed if the hct or hgb returns to normal when the athlete stops exercising for one to two weeks.

Teleologically, are there any benefits to having a dilutional anemia? In the short term (before the body can produce additional red blood cells) it is a rapid way for the body to increase the blood volume and thus increase the cardiac stroke volume (resulting in more blood being pumped through the lungs and muscle circulation per beat). It will also decrease blood viscosity, which may be important to blood flow at the capillary level during exercise.

b) Exertional Hemolysis

• impact (mechanical trauma)
• turbulence in the blood vessels
• acidosis in the working muscle
• elevated temperature in the working muscle

• an increase in the size of the red blood cells in circulation (the MCV; due to the fact that young or new RBCs are bigger in size than older RBCs)
• the reticulocyte count (the cells that have just been formed in the prior few days) is elevated
• the haptoglobin level (haptoglobin is a serum protein that scavenges hemoglobin released from ruptured blood cells) is decreased as it combines with the free hemoglobin (released from the destroyed rbcs into the serum)

• first of all don't forget the other causes of hemolytic (broken blood cell) anemias such as medications, sickle cell trait, and inherited tendencies to have fragile rbcs.
• mitigate impact issues with soft shoes, orthotics, and running on soft surfaces
• slow incremental increases in training seems to help

Normal iron requirements are in the range of 15 mg iron/day. A 2000 Calorie diet has approximately 12 mg of iron. Non meat iron is less well absorbed, thus vegetarians are at increased risk of failing to meet normal needs without the use of iron supplements.

The diagnosis is made by noting a small rbc size (without enough iron, new blood cells are smaller than normal), and finding a low ferritin on additional blood work up.

Treatment is preventative (to minimize the chances of iron deficiency occurring) and after the fact when iron deficiency has already developed. As the body has enough iron stored (on a normal diet) to maintain a normal blood count for many months without any iron in the diet whatsoever, it takes months of poor intake/increase loss to finally become deficient - thus the major role of prevention to avoid getting into a deficient state. And as iron is found in many cellular enzymes (besides rbcs) that are involved in aerobic metabolism (such as mitochondrial oxidative enzymes, cytochromes of the electron transport chain), your athletic performance is often impacted even before there is a significant decrease in the rbc level (see low iron state without anemia below).

Options for prevention include:

• an increase in the intake of meat
• the use of vitamins with a small amount of iron (no more than 15 mg per day)
  • too much iron is bad and can lead to iron overload disease (hemochromatosis) with significant irreversible health impacts
  • the vitamin should be separated from calcium supplements, fiber supplements, and caffeine - all of which can impair absorption
  • vitamin C can actually aid absorption, so drink that glass of orange juice when you take your vitamin.

• ferrous sulfate 325 mg one to three times a day - start slow with one tablet per day as some athletes develop indigestion or bowel problems (both constipation and diarrhea) on iron supplements, and these symptoms are dose related.
• recheck a blood count after two to four weeks of oral to assure the iron is being absorbed. Some people are poor absorbers and may need intravenous iron.
• it will take two to three months to replete your iron stores - then it's time to switch to the prevention program noted above. Do not continue the large treatment doses as the risk of iron overload disease is significant.

D) Low Ferritin Without Anemia

The best approach to eliminate the risk of a low ferritin without anemia in competitive athletes is checking a serum ferritin annually, and treating with iron supplements if it drops below 25. (Glenn Kotz M.D., U.S. national mountain bike team physician has suggested that in high level competitive athletes, "levels below 30-40 produce performance problems even though they're considered normal in sedentary people." And then "taking oral iron supplementation for a month to raise your ferritin levels.")

But there are risks of overtreatment. Higher is not better, when it comes to serum ferritin levels. If one tries to push iron supplements in the face of a normal ferritin - remember 25 is normal for some athletes - the risk of iron overload disease is significantly increased. What about the recreational athletes? A daily multi vitamin which contains 15 mg of iron is low risk and may give you peace of mind. However, with a regular diet, it is probably unnecessary.

DONATING BLOOD

You won't notice much of a change in performance on moderate rides. However if you did intervals, you would notice a decrease in performance until the hemoglobin is replaced. It is a good idea to give blood on a rest day and keep the next few workouts light. And be sure to wait at least 2 weeks before entering a performance event.Over time, repeated blood donation might lead to iron deficiency. USe the prevention measures mentioned above to decrease your risk.

QUESTIONS

Answer:

• If your ferritin and % iron saturation are low, you need iron. So getting the blood tests are step 1.
• If you have normal iron levels, the chemo may be depressing red blood cell production and you may benefit from epo. As long as your hct is less than 50% you may be able to do sanctioned races while on it, but ask. You are in special circumstances with the chemo and might need a waver.
• If the blood test show that you are iron deficient, I'd suggest you use the supplements. It will take too long to get levels up to normal with red meat alone, and you want to feel back to you normal more quickly than that. Once your iron levels are back to normal, you should be able to maintain with diet (even meat free) alone. But an occasional supplement every other day would provide a little insurance from the effects of an unbalanced diet.

The article: "Supplement Worth Re-considering"

"Last week's piece about the potential benefit of iron supplements ("A Supplement Worth Considering") sparked lots of feedback, including e-mails from six medical professionals. In general, the docs expressed great concern about men taking extra iron. Although we included a warning about that and the wisdom of consulting a physician first, they either overlooked the caveat or wanted to emphasize it. Important comments from four doctors are below."

• Gabe Mirkin, M.D. "It is extraordinarily dangerous for a healthy man to take extra iron unless he suffers a deficiency. While women lose iron regularly through menstruation, men lose iron only through bleeding. No man should ever take iron unless his blood test, called ferritin, shows that he is low on iron. Excess iron can deposit in the liver to cause cirrhosis, pancreas to cause diabetes, and the heart to cause a heart attack. Iron is an oxidant that damages tissue. High levels increase risk for heart attacks."
• Lisa Weissmann, M.D. "I am a hematologist (physician specializing in blood disorders) as well as an avid road bike rider. The gentleman in the story had developed iron deficiency anemia from donating blood over a long period of time. For him, the cause of his anemia was iron deficiency, and therefore iron in his case was essential to restore him back to normal. However, anemia can be from a multitude of causes, and iron will not help unless it happens to be iron deficiency. Moreover, iron, by itself, in people who are not iron deficient or anemic, will have no benefit in terms of performance."
• Paul Pagoff, M.D. "Iron deficiency [in men] almost never occurs because of diet deficiency. In men with real iron deficiency the cause is likely blood loss of some sort, including blood donation. If there is no clear explanation then cancer in the intestinal tract needs to be ruled out."
• Steve Weeks, DDS. "Iron is needed for hemoglobin production, as indicated in the article. However, iron is highly conserved in normal males, and dietary requirements for replacement are quite small. Men who have low iron levels as reflected by low hemoglobin or hematocrit should not simply take iron supplements, but should receive medical evaluation for the cause of the deficiency. Some possibilities are gastric ulcer, colon cancer or other form of gastrointestinal bleeding. Less commonly, it is decreased production of red blood cells in the bone marrow owing to the influence of drugs or disease. You did say, correctly, that people starting on supplements should consult their physician. However, it might bear repeating that iron deficiency, especially in men, could be serious and that, as tempting as it is to pop over to the drug store for iron pills, a physician should be involved."

"The bottom line, perhaps, was provided by this e-mail from a roadie who asked that his name not be used: I am not an expert on this but do have an experience regarding the blood issue. My cardiologist, also a bike racer, found out that I donated blood regularly. His immediate response was that sport cyclists 'do not donate blood.' Riders may be better off reducing their blood donations than taking iron supplements."