I recently ventured out on a charity ride from Adelaide to Melbourne. I cycled around 100km a day for 3 days. I didn’t do a lot of training leading up to this (my bad), I did have to buy a road bike and I learnt cleats about 2 weeks before the ride started. By learnt, I took them out for a 20 min ride and fell twice 😉 ha! So obviously I was WELL prepared for such a venture as 300km in 3 days! The first ride I did on this trip was NOT very enjoyable, we started out and it was all fun and games out in the country with beautiful rolling hills and we even had to get on a ferry to cross a river, I mean what an adventure, until I got put into formation and told to stay on the wheel in front of me cause the rider in front would help ‘pull’ me along. THIS IS NOT MY IDEA OF FUN for a new rider, sitting in crash distance from the rider in front and having the rider behind sitting right on your wheel trusting that you actually know what you are doing and spending the ride so focused on the wheel in front that you can’t even enjoy the scenery around you . . . it may save me 20-30% in energy but it cost me 99% in stress . . ha! All to say the rides after this ride were a bit more relaxed and 100 times more enjoyable and so so beautiful! That evening I rode with two of the guys and the sun was setting over the hills and wide open spaces and it was just SO beautiful and that is the reason I have come to love cycling. It reminds me of the times I was in Canada and Holland cycling every day to all sorts of beautiful places (more about the beauty and enjoyment, less about the proper cycling protocol. On the last day I rode from Ballan to Vermont and we were coming through Bacchus Marsh (back in Victoria) and we went done this long hill and it was the funnest thing speeding along, or the morning we woke up before the sun rose and took off on the bikes and got soaked in rain, it was a marvellous ride! I love the adventure of it all!It has come up a few times now the need for a few certain nutritionals when you are doing a lot of exercise. Making sure you are getting adequate macro and micronutrients through diet and supplements when necessary to support and enhance your bodies function. Today I will talk about Iron in Female Athletes.
WHY DO WOMEN ATHLETES NEED IRON?
Iron is a key nutrient for physical activity and iron status is often compromised in women. Iron plays a key role in energy production as a carrier of oxygen, both in the form of Hemoglobin in the blood and Myoglobin in the muscles. Iron is necessary for growth, development, normal cellular function and synthesis of hormones and connective tissue.
Iron loss can occur through sweat, faces and urine, intravascular hemolysis and impaired absorption. In females it was noted that the most Iron was lost in sweat during the first 30 minutes of exercise. It is more often than not noted in women who are long distance runners who experience gastrointestinal losses and foot strike hemolysis. There is more research that needs to be done on this subject.
In research it is of obvious interest whether Recommended Daily Allowance (RDA) of nutrients obtained in diet or supplementation is enough for athletes or should their levels be higher.
Factors to consider in female athletes are, age, menstrual status, vegetarian ect.
Menstruating women have an increased risk for Iron deficiency regardless of training status due to monthly blood loss.
Side Note : People at risk of being low in iron include, Adolescents experiencing a growth spurt especially females once they begin menstruating, inadequate iron intake in diet, strict vegetarians who are only consuming non-heme iron and likely consuming food substances that impair absorption such as polyphenols (tea, wine, certain fruits and vegetables, soy products ect), phytic acid (beans, seeds, nuts, grains), calcium and phosphate salts (dairy, whole grains, nuts, certain meats), soy protein ect.
WHAT IS THE RDA OF IRON?
18mg / day for premenopausal women, a greater need for Iron is seen in pregnancy and lactation and less in children and infants. It is noted although that in increased intake of Iron is not required for physically active women.
WHAT FOODS ARE HIGH IN IRON? AND WHAT IS HEME IRON AND NON-HEME IRON?
Heme Iron : Meat, Poultry, Fish
Non-Heme Iron : Fruits, Vegetables, Grains, Nuts, Seed
WHY SHOULD I GET A BLOOD TEST TO CHECK MY IRON STATUS?
Iron deficiency is not uncommon in female athletes and therefore are advised to supplement with Iron without determining a deficiency through Blood Tests. This is of concern because of the risk of toxicity from Iron overload.
Iron Depletion Occurs in 3 Stages :
- Depletion of stores is identified by Serum ferritin below 12 ug/L. (Serum ferritin can be elevated in response to inflammation, infection, liver disorders, malignancies and exercise induced hemolysis.
- Iron deficient erythropoiesis – identified by increased concentrations of transferrin and reduced transferrin saturation.
- Anaemia. Characterised by microcytic hypochromic (small and pale RBCs) red blood cells and diagnosed as haemoglobin below 12mg/dL in females and 13mg/dL in males.
Also serum levels of soluble transferrin receptor (sTfR) is a gold standard marker for identifying Iron deficiency in its earlier stage as it reflects both iron stores (ferritin) and the rate of erythropoiesis and is less impacted by factors such as inflammation which can mask Iron deficiency.
#Talk to your Health Care Practitioner if you think you have an Iron deficiency or are wanting to start supplementing.
Akabas, S & Dolins, K 2005, Micronutrient requirements of physically active women : what can we learn from Iron?, American Journal of Clinical Nutrition, USA, viewed 15th August 2014,