Skip to main content

«  View All Posts

Physical Therapy

Understanding Relative Energy Deficiency in Sport: Symptoms, Affected Individuals, Risk Factors, and the Role of Physical Therapy

September 15th, 2023 | 6 min. read

Understanding Relative Energy Deficiency in Sport: Symptoms, Affected Individuals, Risk Factors, and the Role of Physical Therapy
Carrie Heidrich

Carrie Heidrich

Licensed Physical Therapist, PT, DPT // EW Motion Therapy Homewood

Print/Save as PDF

Participating in sports and physical activities is essential for maintaining a healthy lifestyle. Athletes are admired for their dedication, endurance, and performance on the field. However, beneath the surface, a hidden issue affects many athletes – Relative Energy Deficiency in Sport (RED-S). This condition can significantly impact an athlete's health and performance, but with proper training and the right care team, any athlete can remain healthy and perform at their best. A physical therapist is often a fantastic ally to ensure your body’s tolerance of your sport - we help our athletes at EW Motion Therapy every day to perform at their best according to the demands of their sport. Even if you decide that our physical therapy isn’t right for you, you can still read on as we explore the symptoms of RED-S, who is most affected, the risk factors associated with the condition, and how physical therapy can play a vital role in its management and prevention. 


Download our Physical Therapy Q&A Here!


What is Relative Energy Deficiency in Sport (RED-S)?

RED-S is a condition that occurs when an athlete does not consume enough energy (calories) to support the energy expenditure associated with their training and daily activities. This energy deficiency can lead to various physical and psychological health problems, ultimately affecting an athlete's performance and overall well-being. RED-S encompasses the female athlete triad phenomenon but recognizes the broader extent low energy availability has on a body and sports performance.


Symptoms of RED-S

Identifying the symptoms of RED-S is crucial for early intervention and management. These symptoms can vary in severity and may include:


  1. Irregular menstrual cycles: In females, one of the hallmark signs of RED-S is irregular or absent menstrual periods, also known as amenorrhea, which occurs due to hormonal imbalances caused by insufficient energy intake.
  2. Decreased bone density: Insufficient energy intake can reduce bone density, making athletes more susceptible to stress fractures and osteoporosis.
  3. Low energy levels: Athletes with RED-S often experience chronic fatigue and low energy levels, hindering their performance and training progress.
  4. Decreased athletic performance: RED-S can impair an athlete's endurance, strength, and overall performance, reducing competitiveness and achievement.
  5. Mood disturbances: Athletes may experience mood swings, irritability, and increased stress due to hormonal imbalances associated with RED-S.
  6. Gastrointestinal problems: Digestive issues, such as constipation, bloating, and discomfort, can arise from inadequate nutrient intake.
  7. Reduced immunity: Athletes with RED-S can be more susceptible to infection and illness.
  8. Cardiovascular problems: Low heart rate is common in those with RED-S, impacting their performance and stamina.


Who is most affected by RED-S?

RED-S can affect athletes of all ages, genders, and sports, but it is more common in certain groups:


  1. Endurance athletes: Athletes in sports requiring prolonged high-intensity training, such as long-distance running or cycling, are at a higher risk due to the substantial energy expenditure involved.
  2. Body composition sports: Athletes in sports where body composition is emphasized, like gymnastics, figure skating, and dance, are particularly vulnerable to RED-S as they may engage in extreme dieting or excessive exercise to maintain a specific physique.
  3. Adolescent athletes: Adolescents still growing and developing are at a greater risk of RED-S as their energy requirements are higher during this period.
  4. Female athletes: While RED-S affects both genders, it was initially recognized in female athletes due to its impact on menstrual function. However, it is increasingly being recognized in male athletes as well.


Risk factors for RED-S

Several factors increase an athlete's risk of developing RED-S:


  1. Caloric restriction: A diet that lacks sufficient calories to meet the energy demands of training and daily life is a primary risk factor for RED-S.
  2. Weight concerns: Athletes who excessively focus on weight control, body composition, or appearance are likelier to engage in restrictive eating behaviors.
  3. Overtraining: Training excessively without adequate rest and recovery can contribute to RED-S by increasing energy expenditure without a corresponding increase in energy intake.
  4. Pressure to perform: Athletes under intense pressure to excel may resort to extreme training and dietary practices to meet performance goals.
  5. Lack of education: Insufficient knowledge about proper nutrition and its role in athletic performance can lead to unintentional energy deficiencies.
  6. Medical conditions: Some conditions, such as gastrointestinal disorders or hormonal imbalances, can contribute to RED-S.


How physical therapy can help

Physical therapy plays a crucial role in the prevention and management of RED-S. Here's how it can benefit athletes:


  1. Assessment and education: Physical therapists can assess athletes’ musculoskeletal health, strength, and flexibility. They can also provide education on the importance of nutrition, energy balance, and the risks associated with RED-S.
  2. Rehabilitation: For athletes who have already developed RED-S-related injuries, physical therapists can design tailored rehabilitation programs to help them regain strength, flexibility, and functionality.
  3. Nutritional guidance: Physical therapists can work alongside registered dietitians to provide athletes with personalized dietary guidance. They can help athletes make informed choices about their diet to meet their energy requirements.
  4. Monitoring and support: Regular check-ins with a physical therapist can help track athletes’ progress, ensuring they are recovering and returning to training safely. This ongoing support can also address any emerging issues promptly.
  5. Stress management: RED-S can be mentally challenging for athletes. Physical therapists can incorporate stress management techniques, such as relaxation exercises and mindfulness, into the treatment plan to support overall well-being.
  6. Collaborative care: Physical therapists often work in multidisciplinary teams that may include sports medicine physicians, dietitians, and mental health professionals. This collaborative approach ensures that all aspects of an athlete's health are addressed.


Preventing RED-S

Prevention is always better than treatment. Athletes can take several steps to reduce their risk of developing RED-S:


  1. Nutritional awareness: Athletes should be educated about their energy needs and proper nutrition. Working with a registered dietitian can help ensure they meet these requirements.
  2. Balanced training: Training plans should be balanced with adequate rest and recovery. Avoid excessive exercise that could lead to increased energy expenditure without sufficient intake.
  3. Regular check-ups: Athletes should have regular health check-ups, including bone density assessments and hormonal evaluations, to detect RED-S early.
  4. Body positivity: Encourage a healthy body image and discourage extreme dieting or restrictive eating behaviors. Promote a focus on performance rather than appearance.


Relative Energy Deficiency in Sport (RED-S) is a serious condition that affects athletes' physical and mental well-being and performance. Recognizing the symptoms, understanding who is most at risk, and identifying the contributing factors are all critical steps in addressing this issue. Physical therapy is pivotal in preventing and managing RED-S, offering athletes the support they need to maintain their health and reach their full potential in their chosen sports. By promoting nutritional awareness, balanced training, and a positive body image, athletes can take proactive steps to reduce their risk of RED-S and enjoy long, healthy, and successful athletic careers. Our physical therapists at EW Motion Therapy can develop a sport-specific treatment plan that addresses your needs and goals, ensuring you are training safely and effectively. If you’re curious about what else physical therapy can do for you, click the button below to download our answers to 20 frequently asked questions.


New call-to-action