Winter is on our doorstep and for many that means a return to hard training.
Pushing the body to the limit while wrapped up warmly on crisp nights is the ground work for subsequent competitive goal making and Summer successes. Therefore, it is important that health and energy levels are high during this period to maximise and sustain high training volumes. Despite this, throughout the Winter months the most common complaint in my clinic is low energy levels.
Clients researching on Dr. Google are often convinced that they have some type of allergy or virus that is preventing them from recovering after tough training, leading to poor energy levels for subsequent sessions. Often, a simple answer such as low iron levels, is the reason the athlete never feels truly sufficiently energised to train.
So, what role does iron play in the body, and how does a lack of this mineral impact on training?
Iron is a critical nutrient needed to transport oxygen around the body facilitating energy production. Inadequate iron levels can reduce the supply of oxygen to the muscle cells, impairing aerobic metabolism and leading to a decrease in endurance, an increase in fatigue and a reduction in overall performance.
Iron is also required for the continuous creation of new red blood cells which deliver the oxygen to the muscles for the production of hormones, connective tissue and for a healthy immune system.
So, you can understand why the body feels exhausted and more open to infection when iron levels are low – particularly when combined with harsh weather and a high training load.
Amazingly, in a recent national survey it was estimated that 1 in 3 Irish women have low iron levels, and 1 in 30 have iron deficiency anemia. In the athletic population the picture is relatively similar, with low iron levels affecting mainly females due to monthly blood loss and a low intake of red meat on a weekly basis. Although iron deficiency is more prevalent in females I often see it in males completing high volumes of training and restricting food intake to maintain or loose weight.
The main cause of low iron levels are simple; lack of dietary intake. This can be due to a restriction in calorific intake to less than 2000 kcal per day or simply failing to eat foods that are high in iron. In endurance athletes, iron deficiency can also be compounded by a small loss of iron through sweating and interestingly, in the faeces. Also, the absorption of iron across the wall of the small intestine tends to be impaired after exercise, which is when we usually eat the majority of our iron rich foods – dinnertime!
In order to prevent iron deficiency, females require 12mg/d and males require 10mg/d of iron. Foods that are high in iron include red meat, organ meat, dark green leafy vegetables, beans, lentils and cereals. Of course it is not only the quantity of iron containing foods that we should focus on, but also the quality of the iron. Iron derived from an animal source is known as haem iron and is absorbed 7 times more easily by the body that its non-haem partner found in all non-animal type foods. So, although you can get adequate iron from non-animal foods you need to eat a hell of a lot more of it than if you were eating animal foods. Take for example a 100g of spinach and 100g of mince meat which contain 6 and 5 mg of iron respectively. However, only a very small quantity of the iron in spinach is absorbed by the body compared to practically all of the iron in the red meat. Of interest also, is the fact that the absorption of non-haem iron can be increased by eating foods rich in haem sources of iron and foods high in Vitamin C.
So what should you do if you think your iron levels are low? The first stop is a trip to your local GP for a blood test. Your ferritin levels, which indicate your body’s stored iron supply, should be greater than 20 ng/ml. Iron levels lower than this, particularly under 15 ng/ml, may require an iron supplement for 4-6 weeks to increase levels.
Hopefully, after reading this article, you can prevent this needless energy sapping condition by just concentrating on eating iron rich foods as listed in the chart below.
Also, be aware that the intake of antacids and anti-inflammatory foods can reduce your body’s ability to absorb iron.
Try this simple delicious black pudding recipe to increase your iron intake at lunch time.