Beef up your iron intake for best performance.

You don't have to be anemic in the classic textbook sense for your iron status to affect your training. Anemia is a deficiency of red blood cells and is measured in various ways--hemoglobin, number of red cells, and hematocrit. These values can all be within normal limits and yet you may be functionally anemic. Research from Cornell University on 42 iron-depleted, non-anemic women with hemoglobin values in the low-normal range who received either a placebo or 100 milligrams of ferrous sulfate (iron supplementation) per day for six weeks in a double blind, randomized trial showed significant differences on the effect of exercise training. These women had relative anemia or very mild anemia that when corrected with iron, improved their athletic performance.

The women trained for 30 minutes a day, five days a week at 75% to 85% of maximum heart rate for the latter four weeks of the study. Baseline iron status and 15K bicycling times were the same for the two groups. Both groups responded to training over the course of the study, but the iron supplementation group increased iron stores and decreased their 15K time trials significantly as compared to the placebo group. The increasing VO2max in the iron supplemented group was more than twice that of the placebo and equal to that of other studies in which subjects trained for much longer periods.

Anemia is relative and if you are a premenopausal competitive female runner, this is something you may wish to discuss with your doctor the next time you have a checkup. If your red blood cell count (this is the usual screen for anemia many women have done annually) is on the low end of normal, it might show up as functional anemia, impairing running performance. Meanwhile, you may want to increase dietary sources of iron to insure that you are running on a full tank and can enjoy maximum progress from your hard training.

In addition to red meat, try dark poultry meat, and other meats that provide "heme" iron (the form your body absorbs best) and fortified breads and cereals that provide non-heme iron. Here is a good non-meat trick: cook your spaghetti sauce in an iron skillet. When cast iron is heated, especially in the presence of an acid such as that found in tomatoes, large amounts of elemental iron leach into the sauce. Since tomatoes are also a good source of vitamin C, and vitamin C is necessary for iron absorption, this cooking method can significantly increase your regular consumption of iron and help keep your iron stores high.

(Journal of Nutrition, 2001, Vol. 131, pp. 676S-690S; Journal of Applied Physiology, 2000, Vol. 88, Issue 3, pp. 1103-1111, E. Randy Eichner MD., Gatorade Sports Science Institute, Sports Science Exchange, 2001, Vol. 14, No. 2)