According to research, having enough iron can be a limiting factor in your performance. Iron deficiency limits your capacity to train and perform and limits aerobic performance, sometimes even in the absence of anemia (a condition where there is a deficiency of red cells or of haemoglobin in the blood, which causes fatigue and pallor).
Iron is such an important mineral for athletic performance as it is a component of haemoglobin, which is essential to transport oxygen from the lungs to the body tissues. In the muscle, it is a component of another protein called myoglobin, which accepts oxygen in order to hold an amount of oxygen to be used by the mitochondria – the powerhouse of the cell. Iron also is a component of the enzymes that is involved in ATP production. ATP can be seen as the “energy currency” of the body, and its job is to store and supply the cell with energy.
People at higher risk for iron deficiency include females (due to menstruation), adolescents (due to rapid growth) and athletes – especially endurance athletes.
Firstly, exercise stimulates an increase in the production of red blood cells and blood vessels. Hard training also leads to inflammation in the tissues. Sweating and the destruction of red blood cells with impact, for example foot strikes while running, also causes iron to be lost.
If you are constantly lethargic and having unexplained decreases in performance for 7 days or more, it is a good idea to go to your general practitioner and get a blood test done in order to test your ferritin levels. The primary way your body stores iron is through ferritin, and if your ferritin levels are too low, you are iron deficient.
The current Recommended Daily Amount for iron is the following:
It is equally important to consider, if not more so, how well the iron that you are consuming is being absorbed, as the amount being taken in. Iron absorption depends on what dietary source it is obtained from. Heme iron is the iron found in meat, fish and poultry, and is more bio-available than nonheme iron, which is found in both plant and animal sources.
Some dietary factors can INHIBIT or ENHANCE your iron absorption:
Iron enhancers:
Iron inhibitors:
*As long as vegans and vegetarians focus on correctly combining enhancers to plant-based iron sources, it certainly is possible to obtain the required amount of daily iron from nonheme, plant based sources (see examples of food sources of iron below)
As you can see, many of the iron inhibitors includes healthy foods. The benefit to eating them, will likely outweigh that of avoiding them. The solution? Focus on including enhancing factors in every iron-containing meal.
It is also important to note that the combined effects of the different enhancers and inhibitors make it difficult to estimate absorption; but the 3 most important factors appear to be the MPF factor, vitamin C sources as enhancers and phytates as inhibitors.
Because iron deficiency anemia can lead to measurable decreases in athletic performance, VO2 max and work capacity, athletes might be tempted to take iron supplements regardless of their current status. Unfortunately, this can be dangerous and lead to hemochromatosis or iron overload. According to an updated review by the ISSN on exercise and sports nutrition, most research shows that iron supplements do not appear to improve aerobic performance unless iron depletion or anemia occurs.
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According to research, having enough iron can be a limiting factor in your performance. Iron deficiency limits your capacity to train and perform and limits aerobic performance, sometimes even in the absence of anemia (a condition where there is a deficiency of red cells or of haemoglobin in the blood, which causes fatigue and pallor).