Anemia and Running

Why has running gotten so difficult? You have been training well, taking care of your body, and tried not to over-train, but now you can barely make it out the door. You may feel irritable and lack the desire to do any form of exercise. If this situation describes you, you may be suffering from a lack of iron, which is known as anemia.

In order run, the human body must have a sufficient amount of iron. Iron plays an essential role in transporting oxygen to the body’s cells and removing carbon dioxide. Training hard requires increased production of red blood cells, which can strain the body’s iron supply and lead to anemia.

To determine if you have anemia, it is important that you have a blood test that measures the amount of hemoglobin and hematocrit in the blood. Hemoglobin is the iron-containing protein in red blood cells and hematocrit is the proportion of the blood that is occupied by red blood cells. Normally, hemoglobin and hematocrit amounts should be more than the following values (from anemia.org):


Age/Sex (yrs) Hemoglobin (g/dL) Hematocrit (%)
Children (0.5-4) < 11.0 < 33
Children (5-12) < 11.5 < 35
Children (12-15) < 12.0 < 36
Adult Men < 13.0 < 39
Non-pregnant Women < 12.0 < 36
Pregnant Women < 11.0 < 33


If your hemoglobin reading is low, the following chart shows the severity of your anemia (from anemia.org):

Severity Hb Range (g/dL) Symptoms Medical Attention
Mild 9.5-13.0 Often no signs or symptoms Commonly remains untreated
Moderate 8.0-9.5 May present with symptoms Requires management to prevent complications from developing
Severe < 8.0 Symptoms usually present May be life threatening and requires prompt management


In order to recover from a case of anemia, it is important to immediately increase your intake of iron. Your doctor may even prescribe iron supplements. It is important that you consume at least 10 miligrams of iron today. Focus on eating red meat, poultry or fish or liver.

Anemia can be one of the most frustrating conditions for runners because it often takes so long to diagnose. Many times runners simply accept being extremely tired as a symptom of training hard when there is actually a medical reason behind the fatigue. The good news is that anemia can be cured quickly if you take time to see your doctor and get tested.


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