Children's Hospital Colorado

The Female Athlete Triad

teen swimmer in competition

For any athlete, good nutrition is essential to performance. Especially in high-output sports like gymnastics, soccer and track, rigorous training demands high energy input to keep the body at its peak.

Unfortunately, many female athletes underestimate their caloric needs, sometimes drastically. This nutrition imbalance can lead to a performance-sapping and potentially dangerous set of symptoms known as the female athlete triad:

  • Low energy availability
  • Menstrual dysfunction
  • Low bone mineral density

Low energy availability

Low energy availability results when the body has more calories going out than coming in. This imbalance can occur when athletes consume too few calories relative to their activity level. It can also be due to disordered eating, which, whether due to societal pressures or other factors, tends to occur more commonly in female athletes.

Menstrual dysfunction

If an adolescent girl has not begun having periods by age 15, misses three consecutive periods or frequently has periods that occur more than 35 days apart, that’s menstrual dysfunction. Persistent low energy availability can affect hormone levels that regulate menstrual cycles. Young female athletes with signs of menstrual dysfunction should see a healthcare provider for further evaluation.

Bone mineral density

Altered hormone levels can also lead to low bone mineral density and ultimately, in severe cases, osteoporosis. Bone mineral density accumulates primarily during childhood and adolescence, so it’s especially important to promote good bone health during this time.

Stress fractures can be an indication of low bone mineral density and should prompt an evaluation for other components of the female athlete triad.

Risk factors for the female athlete triad

Particularly susceptible to the triad are young female athletes who participate in high-energy output sports or sports that emphasize a lean physique, such as:

The following symptoms indicate a female athlete may be struggling with one or more aspects of the triad:

  • Fatigue or decrease in performance
  • Preoccupation with food, weight loss or body image
  • Stress fractures 
  • Depression or low self-esteem

The female athlete triad spectrum

The female athlete triad is a spectrum, with high energy, optimal bone health and normal menstrual cycles on the healthy end, and loss of periods, low energy availability and osteoporosis at the unhealthy end.

The diagram explains the impact of the female athlete triad.

How to prevent and treat the female athlete triad

Proper nutrition is very important to preventing and managing the female athlete triad. To optimize bone health, adolescents should get 1300 milligrams of calcium and 600 international units of vitamin D daily. 

Early recognition is key to treatment. If you notice elements of the female athlete triad, the Sports Medicine Center at Children’s Hospital Colorado can evaluate and help get female athletes back to performing at the top of their game.


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