Why is iron important for exercise?
Iron is used by the body’s muscles to help produce energy. Iron is required for formation of hemoglobin (blood) and myoglobin (muscles) for oxygen transport around the body and muscles cells. Maintaining optimal iron levels may result in increased aerobic capacity and all-round performance.
Active exercisers who enjoy endurance exercise (e.g. running, rowing, cycling, triathlons) need iron to maintain and support energy. Research has shown that reduced iron levels can impact VO2Max and work capacity. VO2 max, also known as maximal oxygen uptake, is the measurement of the maximum amount of oxygen a person can utilize during intense exercise. It is a common measurement used to establish the aerobic endurance of an athlete prior to or during the course of training.
In addition to oxygen transport in the blood, iron also contributes to the reduction of tiredness and fatigue, cognitive function, normal immune function and the formation of red blood cells and hemoglobin. Iron is important for exercise, but we also loose iron through exercise.
Iron can be lost in several ways during exercise:
- Exercisers sweat more than sedentary people, which can lead to higher iron losses.
- Foot strike during running can result in lower iron due to red blood cell damage.
- During exercise the body does not digest food as efficiently and so absorption may be compromised.
- Training for events such as marathons and triathlons will put the body into a state of stress and this can reduce the body’s ability to absorb nutrients efficiently.
Can I always get enough iron from my food if I’m an active exerciser?
You can get iron from food but it may not be absorbed well, and it may not be sufficient to meet your requirements during periods of high training load or if you are an active exerciser. In addition to extra calories, it is important to increase your nutrient intake. You may also decide to curb your intake of caffeine which contain iron inhibiting tannins. Female and vegetarian athletes in particular may find it difficult to meet their daily iron requirements through diet alone.