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  • Writer's pictureDR SARA FORSYTH


Lisa was told by her coach and peers that losing her monthly period was a “normal part of training hard”. She took this at face value until she was diagnosed with a tibial shaft stress fracture. Because of this injury she was assessed by a sports medicine doctor at her university. When the doctor learned she wasn’t getting a regular period she advised Lisa that this was not just a normal part of training and that it was reversible hormonal disturbance. Lisa was referred to a dietician that was familiar with the needs of runners. With a few practical nutrition tips Lisa started getting her regular menstrual cycle again within 6 months. She has not had a stress fracture since.

As women have risen to more prominence in sport, we have become aware of some important issues specific to women. The Female Athlete Triad is a condition of three interrelated issues: energy deficiency, menstrual disturbance and compromised bone health.

The prevalence of menstrual disturbance is higher in runners than in the general population. The prevalence increases with training mileage. These abnormalities can be prevented with balanced energy intake.

The root cause is energy deficiency — an imbalance between the amount of energy taken in and the amount of energy expended during exercise. This can be caused by a conscious restriction of food intake (disordered eating) or non-intentional under-consumption of calories. Athletes simply don’t realize how much energy they expend during workouts and they don’t eat enough to maintain a healthy weight. The body perceives too great of a gap between energy intake and expenditure, which can lead to issues with the reproductive system. In young athletes, the onset of periods may be delayed. Older women may experience too few menstrual periods (oligomenorrhea), or even more worrisome, no period for several cycles in a row (amenorrhea).

Runners have lots of bone turnover due to the weight bearing and repetitive nature of the sport. This makes bone stronger as long as the right ingredients are available. If the hormones required to stimulate formation of bone are not available one may lose bone faster than it can be replaced. This predisposes one to stress fractures and ultimately low bone mass. This situation is especially concerning when females are within the age span of peak bone-building years (puberty to approximately 20). If bone accumulation is reduced during this critical period they will not build as much bone mass as expected and this appears to be permanent.

What puts a woman at risk for development of the Female Athlete Triad?

The initial factor is an energy imbalance. This may be from a rigorous training schedule without adequate nutrition, or from disordered eating stemming from beliefs around body image. Female athletes who diet from a young age or engage in frequent attempts to lose weight or decrease body fat are at obvious risk.

An athlete does not need to have all three components of the triad to be at risk for related health problems. Athletes with risk factors, or early signs of the triad, need to be assessed by a sports medicine professional. It is important for athletes to know that not getting menstrual periods is not a “normal” part of training and can easily be avoided.

Luckily, this condition is easily prevented especially if athletes, coaches and parents of younger athletes are informed and aware. The cornerstone of prevention is developing healthy relationships with food and training from a young age. These healthy habits will last a lifetime and ensure optimum reproductive and bone health and prevent many overuse injuries associated with consuming too few calories leading to inadequate recovery from training.

  • Prevention

  • Education of coaches, parents and athletes

  • Early detection of risk factors

  • Ensuring adequate calorie intake that balances with training schedule

  • Education around quality nutrition and timing of nutrition

  • Seeking advice from a medical professional early on

  • Remembering to enjoy training and food!


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