Tuesday, February 8, 2011

Iron Maiden

Are you training hard and  experiencing poor or mediocre race results? Do you feel sluggish or tired even a few kilometers/miles into your run?  Low iron levels could be a possible culprit. 

Iron levels and running is a hot topic for runners. IMO,  it is an important issue for all runners, but especially important for female runners. 

I have personally been plagued with low iron stores before. As a mostly vegetarian runner (no red meat or pork and only the occasional taste of chicken, turkey, and fish),  I am at risk for having my iron levels drop again.   In fact, I always start to worry about my iron levels when I am mid marathon training cycle.  This constant awareness caused me to stumble across this good article here about low iron levels and the impact it has on running.

Why is Iron Important?

As runners, iron is vital as it is a key component to our oxygen transporting molecule, hemoglobin.  It also has several metabolic roles in our body.  It is also cited as the largest nutrient deficiency amongst Americans (I couldn't find a statistic about Canada,  but I am sure it is a similar issue).
Reasons for Iron Deficiencies in Runners

1. Foot Strike Hemolysis
This basically means that as your foot strikes the ground,  the impact can cause hemolysis (damage or death) to your red blood cells.  You do regenerate your blood cells,  but excessive hemolysis can cause your iron level (hemoglobin) and iron stores (ferritin) to drop.

2. Sweat and Urine
Iron is lost is sweat and urine,  this loss is compounded by athletes that sweat alot.  Interestingly, iron is lost through the GI track in runners that train in hot humid climates (definitely not Ontario at the moment -22C tonight during my hill workout!!)  Still even in the cold, I tend to sweat alot, and often come home with soaked clothes.

3. Low levels of iron in your diet
Red meat and dark poultry tend to be good sources of iron (however, I believe you do not need to eat meat to have sufficient iron levels, you just need to be more conscious). Many endurance athletes eat carbohydrate rich diets that have lower levels of meat or other iron sources.

4. Poor iron absorption
Iron is a finicky mineral.  Certain substances such as coffee impede iron absorption, so although you consume the iron,  you are not absorbing it.

5. Blood volume
Endurance athletes have a higher blood level,  making the iron a more dilute concentration in our bloodstream.

6. Menstrual Cycle
This one is pretty self explanatory for us ladies!

Tips for combating/preventing low iron levels:

a) Get your iron checked.
 This involves two measurements:
i) Hemoglobin:  Normal hemoglobin concentration ranges from 14 to 18 grams per 100 ml of blood for men, and 12 to 16 grams per 100 ml of blood for women.
ii) Iron stores (ferritin): Normal ferritin levels are 10-200 ng/ml for women and 10-300 ng/ml for men. Training is seriously affected when ferritin levels drop below 20 ng/ml (ask your doctor for your lab results)!

b) Eat more iron containing foods
 Meat, oysters, dark green leafy vegetables, legumes, enriched breads and cereals are example of foods that are rich in iron.  You can also cook your food with cast iron pans to help with iron levels (I use my cast iron pan all the time!!)

c) Eat foods that help iron absorption
Foods high in vitamin C such as orange juice help iron absorption.

d) Avoid foods that impede iron absorption
Caffeine is a culprit for impeding iron absorption. Anyone know of some others?

e) Take an iron supplement
Note of caution: It is best to have your levels checked before taking a supplement,  as excessive iron levels can be toxic to your liver. 

I don't really want to resort to excessive meat in my diet,  and having not eaten red meat or pork for seven years,  I can't see myself returning to it.  However the article mentions elite marathoner Deena Castor. She eats alot of red meat in her diet,  and has really good iron levels,  which she attributes to her excellent performance. Interesting food for thought.

Are low iron levels a concern for you?  How do you keep your iron levels normal? 

Thanks for reading!!