Female Athlete Underfueling: The Silent Performance Killer
In the world of athletics, both professionally and recreationally, underfueling is a widespread yet often overlooked issue, especially amongst women. Whether intentional or unintentional (e.g. not knowing your needs), not eating enough to support training demands can have serious consequences on health, performance, and longevity in the sport. Understanding the risks and recognizing the signs are crucial for athletes looking to perform at their best while maintaining long-term health.
The Prevalence of Underfueling in Female Athletes
Underfueling can occur in any sport, but endurance, aesthetic, and weight-class sports show particularly high rates of energy deficiency. Research suggests that up to 47% of female athletes experience low energy availability (LEA), a state where caloric intake is insufficient to support both daily physiological functions and training demands. The Female Athlete Triad and Relative Energy Deficiency in Sport (RED-S) are well-documented conditions resulting from chronic underfueling, affecting bone health, hormonal balance, and overall well-being.
The Long-Term Consequences of Underfueling
Failing to meet energy demands doesn't just impact short-term performance; it has profound long-term effects:
Hormonal Disruptions: Chronic underfueling can lead to irregular or absent menstrual cycles, reduced estrogen levels, and increased risk of infertility.
Bone Health Decline: Without adequate nutrition, the body leaches calcium from bones, leading to osteopenia and osteoporosis, increasing fracture risk. This is compounded by suppressed estrogen.
Metabolic Adaptations: The body slows metabolism to conserve energy, making fat loss harder (or weight gain easier) and reducing overall energy levels. Increasing calories requires a strategic re-conditioning of metabolism.
Cardiovascular Risks: Underfueling affects heart health through a lack of important nutrients and hormonal imbalances, increasing the risk of blood pressure issues, arrhythmias, and heart disease.
Mental and Emotional Struggles: Anxiety, depression, and irritability can increase, along with disordered eating patterns.
Are You Underfueling?
If you’re unsure whether you're eating enough to support your training and health, ask yourself these questions:
Do you frequently feel fatigued or have trouble recovering after workouts?
Have you noticed a decrease in strength, endurance, or performance?
Are you experiencing irregular or missing menstrual cycles?
Do you often feel cold, even in warm environments?
Do you restrict food groups or feel guilt around eating certain foods?
Have you experienced increased stress fractures or injuries?
Do you suffer from sleep disturbances, mood swings, or difficulty concentrating?
If you answered “yes” to two or more, you may need to assess your nutrition intake and seek professional guidance.
How to Address Underfueling
1. Increase Caloric Intake
Ensure you're consuming enough calories to match your activity level. Slowly work on increasing portion sizes of staple foods you are currently using. Keep it simple, start small.
2. Prioritize Protein and Healthy Fats
Protein supports muscle repair and recovery, while fats help with hormonal balance. Include lean meats, fish, eggs, dairy, nuts, seeds, and avocado. Research tells us that a diet with about 20% of calories coming from healthy fats, and a minimum of 1.2g/kg up to 2.4g/kg of protein daily is optimal, pending the person and their activity level/recovery requirements.
3. Time Your Nutrition Strategically
Eat pre- and post-workout meals to support energy levels and recovery. A carbohydrate-rich snack before training, and a carbohydrate loaded, protein-packed meal afterward can make a huge difference.
4. Monitor Your Menstrual Cycle
Your menstrual cycle is a key indicator of health. If it’s irregular or missing, consider increasing your food intake and consulting a healthcare professional. Losing your period is not an indicator of good performance and optimal training.
5. Seek Professional Guidance
A professional can help tailor a fueling plan specific to your needs, for both performance and long-term health.
If you suspect you’re underfueling, take action now—your body and future self will thank you!
Holtzman, N., & Ackerman, K. E. (2021). Medical complications of relative energy deficiency in sport in female athletes. The Journal of Clinical Endocrinology & Metabolism, 106(10), e3823-e3837.
Mountjoy, M., Sundgot-Borgen, J., Burke, L., Ackerman, K. E., Blauwet, C., Constantini, N., ... & Budgett, R. (2018). International Olympic Committee (IOC) consensus statement on relative energy deficiency in sport (RED-S): 2018 update. British Journal of Sports Medicine, 52(11), 687-697.
Grabia, M., Perkowski, J., Socha, K., & Markiewicz-Żukowska, R. (2024). Female athlete triad and relative energy deficiency in sport (REDs): Nutritional management. Nutrients, 16(3), 359.
