How do you go about fixing it?

Your blood test shows an iron deficiency

The first step is dietary. Iron in food comes in two forms: heme – found in animal flesh, such as red meats, liver and other organ meats, chicken and fish – is well absorbed; and non-heme, in plant based foods, which is generally poorly absorbed by the body. Vegans and vegetarians are able to get enough dietary iron, but it might require some more planning or food knowledge. A sports dietitian should be able to help you with this.

As well as the iron content of the food, you want to consider the timing or intake, as well as other foods you eat with it that either boost or block absorption. For instance, hepcidin levels are low in the morning and take a little time to rise after a hard workout. That period following a morning training session may be a good time to focus on iron-rich foods or to include your supplement, if that is what your doctor has recommended. Vitamin C enhances iron absorption, so include some vegetables or some orange juice at that time. Similarly, avoid drinking tea and coffee with your meals as the tannins can reduce iron absorption by as much as 50 per cent. The other important dietary factor is to simply be eating enough – enough calories, that are well timed to support training, recovery, growth and health.

The good news for outdoor athletes, is that adequate vitamin D, of which sunlight is the best source, also appears to play a role in enhancing iron absorption by reducing hepcidin levels and/or associated inflammatory markers. In winter, though, this may be something you also want to consider, or even have tested.