Athletes often experience irregular or missed periods, which is a condition known as amenorrhea. There are several reasons why amenorrhea is common among female athletes:
Low Body Fat
Many athletes maintain a very low percentage of body fat for optimal performance. For women, having too little body fat signals to the body that food is scarce, which can cause a disruption in menstrual cycles. Amenorrhea often occurs when women have under 15% body fat.
| Sport | Average Body Fat % |
|---|---|
| Gymnastics | 12-16% |
| Figure Skating | 14-20% |
| Swimming | 14-24% |
| Track & Field | 14-20% |
As you can see, many elite female athletes maintain very low body fat percentages. This signals to the body to conserve energy by stopping non-vital functions like menstruation.
High Training Volumes
Intense training and high mileage are demanding on the body. Athletes may train over 20 hours per week with extensive endurance and strength training. This metabolic stress can cause hormonal shifts that disrupt ovulation and menstruation. Studies show amenorrhea is more common in athletes who:
- Train over 16 hours per week
- Run over 30 miles per week (for runners)
- Burn over 900 calories per day through exercise
The physical stress of heavy training loads sends signals to the body to focus its energy on exercise performance rather than reproductive functions.
Low Calorie Intake
Many female athletes restrict calories to stay lean or maintain a light physique for their sport. However, consuming too few calories can cause the body to shut down non-essential processes like menstruation. Here are some signs an athlete may be underfueling:
- Calorie intake under 30 calories per kg of body weight
- Missing periods for over 3 months
- Feeling cold, moody, or excessively fatigued
- Increased risk of bone injuries
Athletes need sufficient calories not only for performance but also for overall health. Falling below the calorie threshold required for a normal menstrual cycle is a clear sign more fuel is needed.
High Stress Levels
Athletes face immense physical and psychological stress. The daily demands of training, competition, recovery, and performance pressure can raise cortisol and other hormones that influence menstruation. Amenorrhea is more common among athletes who:
- Compete at high levels like professional or collegiate sports
- Cut weight or restrict food intake before competition
- Suffer from anxiety, depression, or disordered eating
- Struggle with overtraining injuries and burnout
Learning to manage stress through proper rest, nutrition, and mental health support can help prevent stress-induced menstrual dysfunction.
Sudden Changes in Training Habits
Menstrual cycles can be disrupted by sudden changes in exercise routines. For example, an athlete might experience amenorrhea if she:
- Rapidly increases training volume, intensity, or mileage
- Starts a new, demanding training program
- Changes teams or coaches, leading to different training demands
- Returns to training after time off due to injury or the off-season
Gradual, periodized training programs allow the body to adapt without overly stressing hormones. Monitoring cycles throughout training changes helps identify any issues early.
Effects of Amenorrhea
Missing periods may seem convenient, but amenorrhea can have serious consequences. Athletes who lose periods face higher risk of:
- Bone injuries: Estrogen from ovulation helps maintain strong bones. Lack of estrogen can lead to weak, brittle bones.
- Stress fractures: These overuse bone injuries are 2-4 times more likely in amenorrheic athletes.
- Osteoporosis: Lost bone density may not be recoverable, increasing lifelong fracture risk.
- Infertility: Chronic amenorrhea can prevent conceiving and carrying a pregnancy later on.
- Heart problems: Hormonal issues increase cardiac risks like arrhythmia and blood clots.
Amenorrhea is the body’s way of signaling it is under too much physical stress for normal functioning. Ignoring it can lead to long-term health consequences.
Recovering Normal Cycles
There are several strategies athletes can use to resume a normal menstrual cycle:
- Increase calorie intake – aim for at least 30 calories per kg of body weight
- Reduce training volume and intensity if excessive
- Gain some body fat – aim for 18-22% body fat
- Minimize other stresses and get adequate rest
- See a doctor or sports medicine specialist
- Consider hormone therapy short-term if underlying issues have been addressed
With appropriate changes to diet, training, and lifestyle, amenorrhea can often be reversed. This allows the body to recover and reduces injury and health risks.
Key Takeaways
- Female athletes often experience amenorrhea due to low body fat, intense training, restricted eating, stress, and sudden training changes.
- Absent periods indicate the body is under too much physical stress from exercise training.
- Amenorrhea increases risks of bone injuries, osteoporosis, infertility, and heart problems in athletes.
- Adjustments to diet, training, and lifestyle can help restore normal menstrual function.
- Seeing a sports medicine doctor can help diagnose the cause and monitor progress.
Amenorrhea should not be ignored or considered normal for female athletes. Supporting overall health and reducing exercise stress is key to recovering normal cycles and avoiding associated medical risks.
The Bottom Line
Female athletes often develop exercise-induced amenorrhea due to the metabolic demands and stress of sports training. Losing periods indicates the body is being pushed too hard and needs more energy and rest. Restoring normal menstruation reduces an athlete’s injury risk and long-term health consequences. Support from coaches and sports medicine staff can help determine if training volumes, intensity, nutrition, and stresses need adjusting to allow proper hormonal functioning.