Signs of underfueling and overtraining in a female athlete can sometimes be hard to recognize. When an athlete feels fatigued, or experiences mood changes, various symptoms can sometimes be rationalized away as possible side effects of stress. One hallmark symptom of underfueling and overtraining in the female athlete however, that cannot and should not be missed, is a change in the menstrual cycle.

Unfortunately, female athletes are often unaware of the connection and are surprised during nutrition consults when I ask questions about their menstrual cycle. Here, we’ll explain the warning signs of a dysfunctional menstrual cycle and why a healthy regular menstrual cycle is critical to long-term health and performance. We’ll then share some guidance for female athletes looking to regain and maintain their cycle.

What are the warning signs of menstrual dysfunction?
Unlike other signs of underfueling and overtraining, warning signs for menstrual dysfunction can be visibly observed and communicated to a professional such as an OBGYN. It is important to note that birth control can often mask these symptoms. Whether or not you are on birth control, it is imperative to communicate with your doctor regarding concerns before assuming that menstrual function is intact.

Signs of a disrupted menstrual cycle often include one or more of the following symptoms:

  • No menstruation by the age of 16
  • Missed three consecutive periods
  • Periods occurring at intervals greater than 35 days
  • Irregular periods

What are the consequences?
Females without regular periods will experience changes in estrogen and other hormones that are critical to bone density, long-term health and athletic performance. Bones are living, growing tissue that are constantly being built and broken down by your body. An athlete with adequate nutrition, appropriate levels of physical activity, weight bearing exercise and optimized hormone levels will be able to build stronger, denser bones every year. The athlete with stronger bones will be able to produce and reduce greater forces during bouts of exercise, which can contribute to gains in strength and speed required to compete in elite level sports. Athletes without their period will lack estrogen, related hormones and nutrients required to achieve these health and performance improvements. This can result in decreased overall bone density, increased risk of injury, and substantially reduced capacity for strength and speed. Since peak bone mass is achieved by around age 30, athletes with lower overall density can also experience greater risk for fractures and early onset of bone diseases such as osteopenia and osteoporosis.

Lastly, women who experience prolonged periods of menstrual dysfunction and low estrogen, can experience a wide range of additional physical and mental health consequences such as increased risk of irreversible infertility, impaired working muscles and metabolism, and increased risk for low self-esteem, depression and anxiety disorders.

Why does this happen?
Menstrual dysfunction often occurs when an athlete’s body has insufficient energy availability, contributing to body fat stores that are too low to support hormonal homeostasis. Energy availability is represented by the amount of dietary energy (calories) remaining after the energy costs associated with metabolism, bodily functions and exercise training are accounted for each day. A longstanding pattern of dieting or restricted food intake and/or a sustained high level of exercise and training contributes to low energy availability and weight loss. This reality links eating disorders, disordered eating behaviors and compulsive exercise to low energy availability.

What does low energy availability look like?
In addition to the menstrual irregularities, signs of low energy availability can include a dietary recall from an experienced sports dietitian and/or assessment of energy expenditure and laboratory data by an exercise physiologist indicating low energy availability. Additionally a BMI less than 18.5 in adults, weight less than 85% of expected body weight in adolescents, or recent weight loss of more than 10% of total body weight in one month are also strongly linked to low energy availability. Numbers alone, however, often do not provide a full picture. Just because an athlete has a stable weight or “normal BMI” does not guarantee that their body has sufficient energy availability to support menstrual function. Many issues are frequently overlooked because people do not typically associate particular body types with disorders, but low energy availability can occur in women regardless of body type, shape and outward appearance.

What treatment is recommended?
Preventing and correcting menstrual dysfunction requires striking a careful balance between energy intake (nutrition) and energy expenditure (exercise). The first step in prevention is education and awareness. Know your needs as a competitive athlete. Consulting with a multidisciplinary sports medicine team of experts including a physician, dietitian and exercise science professional can help you better understand the unique challenges, requirements and high demands of competitive sports. If disordered eating or an eating disorder (ED) is a contributing factor, the added services of a mental health counselor or sport psychologist are needed. Evaluation by a team of professionals can help determine if you are experiencing or are at risk for menstrual dysfunction and the team can create individualized treatment strategies.

If you know an athlete exhibiting any of these signs or symptoms, it is best to act sooner rather than later since timely intervention can make a difference in terms of recovery. A multidisciplinary team of specialized eating disorder therapists and dietitians who understand sport can help athletes build better relationships with their bodies, their training regimens and with food. Athletes who surround themselves with experts who understand the careful balance of nutrition in relation to training demands will be better equipped to avoid these pitfalls that can have lifelong consequences.

To learn more about resources for athletes and disordered eating, check out the Walden GOALS program.


Matt is a licensed registered dietitian nutritionist and certified strength and conditioning specialist. He is a nutritionist and exercise science advisor for the Walden GOALS program. Matt devoted the early part of his career to refining the art of training elite collegiate and professional athletes. In graduate school, he developed expertise in nutrition, behavior change and eating disorders. Matt now devotes his practice to translating nutrition and exercise science into practical solutions. As a lead member of the GOALS team, Matt is known for his dedication to educating and empowering athletes of all backgrounds to facilitate a full and meaningful recovery from disordered eating. Matt holds a B.S. degree in Kinesiology from the Honors College at The University of Massachusetts Amherst, a master’s degree in Applied Exercise Physiology and Nutrition from Columbia University and was a dietetic intern at Boston’s Brigham and Women’s Hospital.