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by Matheson C

Women Running Marathons: Weighing the Risks and Benefits

IMAGE Many women are undertaking the challenge of a marathon either as a motivation to get in shape or to take on something new. Physical activity is a healthy pursuit, but marathons are a bit beyond the scope of a normal exercise routine. The intense physical requirements of training and the marathon itself may lead to more harm than good if you go about it the wrong way. In women, overtraining can lead to health problems called the female athlete triad. The following will help you fuel your intense training while avoiding harm to your body.

Benefits of Running a Marathon

It is generally not dangerous for women to train for and run in marathons when the training is done right. Evidence shows that marathon runners (and long-distance runners) have decreased risk of :
The more your run, the better your chances of decreasing the risk of these diseases. But, there can be too much of a good thing.

Knowing the Triad

Certain training habits can lead to a particular set of health problems in women known as the Female Athlete Triad. The triad consists of 3 elements that affect your overall health and your ability to become a top-notch marathon runner:
  • Poor nutrition—particularly not eating enough in relation to training
  • Loss of monthly periods (amenorrhea)
  • Loss of bone density, which can lead to osteoporosis
Knowing the pitfalls that can lead to this triad is the best way to stay healthy. Here is more detailed information about the triad.

Disordered Eating

Disordered eating associated with marathon training is from not eating enough to meet the demands of training. It should not be confused with an eating disorder like anorexia nervosa or bulimia nervosa where a person deliberately does not consume enough food. Too little food or poor nutrition choices will limit the fuel your body has to function. As a result, your body will need to tap into your own body tissue (like muscle) for fuel. This will impair your body's ability to work at its best and slow your recovery from intense workouts.
Intense training will need proper nutritional support. In other words, your body will need to replace the extra calories that it burns during training. Unrealistic weight or appearance goals can also create bad nutritional behaviors. Work with a professional to help find a balance to your goals. Tips that may help include:
  • Get nutrition advice from a dietitian or physician.
  • Talk to your doctor about a goal weight. Find balance to learn how to control it.
  • Therapy may be necessary to manage stress triggers, provide emotional support, and to monitor dietary changes.
Once good eating habits are established, the next 2 pieces of the triad will be easier to manage.


Amenorrhea varies with the intensity of physical activity. The amenorrhea of the female athlete triad is caused by a combination of too much exercise and lack of adequate nutrition. The intense demands on your body combined with lack of fuel causes hormonal imbalances that can lead to amenorrhea.
There are a variety of other reasons why amenorrhea may develop. Discuss any changes in your period with your doctor. The doctor will need to know about your current training regimen to help determine if that is a factor in the amenorrhea.
Amenorrhea itself may not cause problems but it may be a sign of imbalance. Your doctor can help you find the cause of the imbalance. In addition, lack of hormones (mainly estrogen) can put you at risk for osteoporosis.


The combination of poor nutrition and amenorrhea can also cause changes in your bones. It can cause a depletion in substances that help to build and repair bone. The bone changes can eventually lead to osteoporosis. This increases your risk of fractures. It can be particularly dangerous when bones are weakened in younger women. Women that do not build strong bones when they are young are much more likely to have problems when they are older.

Eat Enough and Eat Well

A great benefit to training for a marathon is that you can eat more—in fact, you have to so you can replace all the calories you burn during training. Be careful to avoid this first point of the female athlete triad, and make sure your diet is adequate to meet your body's increased demands.
Make sure you get enough calcium while training, in fact consider adding calcium to your daily routine. Protein and iron are also extremely important. If you are not a vegetarian, lean red meat is a great source of both protein and iron. Vegetarians should look for alternative means of getting adequate iron and protein.
If you are still concerned about low estrogen levels and losing bone density, talk to your doctor about taking oral contraceptives or other hormones. Research supports that oral contraceptives may be associated with increased bone density and less risk of a stress fracture. Oral contraceptives have other side effects, so it is important to weigh out the risks and benefits with your doctor.
The most important thing is awareness. Listen to your body and give it what it needs. If you train right and eat well, you can prevent serious health problems and conquer a few marathons along the way.


American College of Sports Medicine
Female Athlete Triad Coalition


Dietitians of Canada
Public Health Agency of Canada


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