Female athletes are at a higher risk than their male counterparts of developing iron deficiency, and as such should be very wary of misguided dietary practices where energy intake is cut to extraordinarily low levels in an attempt to drop body fat quickly. In fact, highly restrictive dietary practices are more likely to chew through valuable muscle mass lowering metabolic rates and making it harder to tap into fat stores.
Through the human performance lab at Wesley Corporate Health I have seen a number of clients (male and female) who have been involved in yoyo dieting style eating habits who now struggle with chronically lowered metabolic rates as a consequence, but that’s a different story, back to iron stores………..
The human body needs iron to transport oxygen around the body to service the demands of working muscles, particularly in endurance based sports like triathlon in which the energy demands are almost exclusively reliant on aerobic (with oxygen) metabolism.
Iron is lost to the body through via a number of different processes including; (i) perspiration, (ii) urine and faeces, (iv) heel strike haemolysis of red blood cells (i.e. Destroying red blood cells via the impact of the heel against the ground when running), (v) micro-trauma to the GI tract, and (vi) menstrual blood losses in females.
The symptoms of iron deficiency may include impaired athletic performance, tiredness/lethargy, headaches, cramps and shortness of breath.
It’s recommended that female endurance athletes have blood tests every six to 12 months to check their iron status. For the endurance athlete, even if all other indicators of iron status fall within the normal range (e.g. Hematocrit, haemoglobin levels, etc.), be particularly attentive to serum ferritin stores. If these are low (or on the low end of normal) this can be indicative of a latent amenia. The AIS used to have a policy that would supplement athletes with oral iron supplementation if serum ferritin levels fell below 30. I‟ve personally seen female, vegetarian endurance athletes present with serum ferritin levels of 5-6 ug/L.
So what can you do to offset such iron losses?
The best way to prevent iron deficiency is to ensure an adequate iron rich diet, particularly “haem” iron, which is found from animal sources, as it is far better absorbed by the body. To help with making such choices a well-versed sports dietician is invaluable. Some studies suggest that heel strike haemolysis can be alleviated by running in well-cushioned shoes and choosing to run on softer surfaces such as bush trails or lawns.
Rod Cedaro, sports coach