Running is a universal sport, where distinctions are made by speed, ability and ambition rather than by sex. Nevertheless, there are some fundamental issues of physiology and biology that impact only on women.Anemia
Female runners are at a greater risk of anemia than sedentary women, due to both menstrual blood loss and the break down of red blood cells when you exercise. This is particularly the case if you're vegetarian. All female runners should aim to consume at least 15mg of iron every day.
Running and menstruation
Your period can affect how you feel when you go out for a run, but it should not stop you training. In fact, running during your period can actually relieve cramps - as your brain releases feel-good endorphins that reduce the pain - and also alleviate breast tenderness and fluid retention. Do not worry if it feels harder to run in the week before your period: this is the time when the hormone progesterone peaks, making for a higher-than normal breathing rate. Regular running can also help to reduce the changes in mood that are often associated with premenstrual syndrome.
Amenorrhoea
In some extreme cases, particularly in elite athletes who are on hard training regimes, running can lead to amenorrhoea (the absence of a monthly period). It's due to a lack of oestrogen in your body, caused by over-training, low body fat and inadequate nutrition. The hormone oestrogen is essential for the replacement of bone minerals in your body, and a deficiency raises your risk of stress fractures and osteoporosis. If you start to miss periods - and know you are not pregnant - consider your diet and training levels carefully.
