Healthy
Blog

RED-S: The Silent Condition Sabotaging Your Sports Performance

Monday, March 10, 2025

What is RED-S?

RED-S (Relative Energy Deficiency in Sport) occurs when an athlete doesn't consume enough energy (calories) to meet the demands of their training, performance, and essential bodily functions. This condition can affect both male and female athletes and goes beyond just an energy deficit to impact overall health, performance, and well-being.

Typically, RED-S develops when an athlete’s energy intake falls short of what their body needs for training, recovery, and daily activities. This energy gap often arises from a combination of restrictive eating, excessive exercise, or poor nutrition. A study by Cabre and colleagues highlighted the importance of maintaining an energy availability of at least 45 kcal per kilogram of lean body mass per day to prevent RED-S.

Although RED-S is commonly seen in sports that emphasise low body weight, such as gymnastics, running, or cycling, it can affect athletes in any sport.

Recognising and addressing energy deficiency early is crucial to maintaining both performance and long-term health. 

What are the RED-S Risk Factors?

The risk factors for RED-S are varied and understanding them is key to preventing this condition. Here are some of the most common risk factors:

• High-Intensity or Endurance Training: Athletes who engage in excessive training or have high energy demands without sufficient recovery are at risk of burning more energy than they consume. Endurance sports such as running, cycling, and swimming, which require prolonged energy expenditure, often lead to energy deficits if food intake doesn't adequately match these demands.
• Restrictive Eating: Low-calorie diets, eating disorders (such as anorexia, bulimia, or binge eating), and unhealthy relationships with food can create significant energy imbalances. Athletes who fail to consume enough calories to support both their resting metabolic rate and physical activity are more likely to develop RED-S.
• Pressure to Maintain Low Body Weight: In certain sports, athletes may feel pressure to maintain a specific body type or weight, leading them to restrict their food intake. This can be exacerbated by societal pressures and social media, where body image ideals often contribute to unhealthy practices that increase the risk of energy deficiency.
• Psychological Stress and Perfectionism: Athletes who experience high levels of psychological stress, anxiety, or perfectionistic tendencies are more vulnerable to RED-S. The desire to push physical limits or maintain strict physical standards can lead to overtraining and poor nutritional habits.
• Inadequate Recovery or Overtraining: Athletes who push themselves too hard without allowing for adequate recovery are at greater risk. Overtraining reduces energy availability and can lead to physical and psychological burnout, both of which contribute to the development of RED-S.
• Adolescent and Young Athletes (particularly women): Younger athletes, especially those going through puberty, are more susceptible to RED-S due to the demands of growth and sport participation. During periods of rapid growth, energy needs increase, and failing to meet these demands can raise the risk of RED-S. Women are particularly vulnerable because the energy demands required to maintain menstruation also need to be met.

Recognising these risk factors is essential for preventing RED-S and supporting athletes in maintaining their overall health and performance.

What are the Symptoms of RED-S?

The symptoms of RED-S can vary widely, but they often impact both physical and mental well-being. Some common signs to look out for include:

• Decreased Athletic Performance and Increased Fatigue: One of the first signs of RED-S is a noticeable decline in performance, coupled with constant fatigue that doesn't improve with rest.
• Irregular or Absent Menstruation in Females: A disruption in the menstrual cycle, including missed periods or completely absent menstruation, is a key indicator of RED-S, especially in female athletes.
• Decreased Bone Mineral Density: Prolonged energy deficiency can lead to lower bone density, which increases the risk of fractures and long-term bone health issues.
• Hormonal Imbalances: RED-S often causes hormonal disruptions, including a reduction in thyroid function, which can affect metabolism and overall energy levels.
• Increased Injury Rates: Athletes with RED-S are more prone to injuries, as the body’s ability to repair and recover is compromised by inadequate energy availability.
• Mood Disturbances: Feelings of depression, anxiety, and irritability are common in athletes with RED-S, as the condition can affect mental health as well as physical health.
• Gastrointestinal Issues or Trouble Sleeping: RED-S can lead to digestive problems, such as bloating or constipation, and cause difficulty with sleep, which further exacerbates fatigue and recovery.
  

Once diagnosed, how is RED-S managed?

Managing RED-S (Relative Energy Deficiency in Sport) involves restoring energy balance and ensuring that an athlete receives adequate nutrition to support both their athletic performance and overall health. Several key strategies are crucial for addressing this condition:

• Nutrition Intervention: A well-balanced diet rich in carbohydrates, proteins, fats, vitamins, and minerals is essential to restore energy balance. Collaborating with a sports dietitian can help create a nutrition plan tailored to the athlete's specific needs, ensuring they consume enough calories to support both their physical activity and general health.
• Gradual Return to Exercise: Athletes should gradually reduce the intensity and volume of their exercise to allow for proper recovery. Energy intake must be sufficient to support this reduction in exercise load. Temporarily decreasing high-intensity training or modifying exercise routines will help the body heal and rebuild energy reserves.
• Psychological Support: For athletes dealing with disordered eating or body image issues, psychological counselling is a vital component of recovery. Cognitive-behavioural therapy (CBT) is particularly effective for addressing disordered eating behaviours or performance anxiety, providing athletes with the mental tools to navigate their recovery process.
• Multidisciplinary Involvement: Successfully managing RED-S requires a collaborative approach involving a team of healthcare professionals. This may include sports nutritionists, psychologists, physicians, coaches, and trainers, all working together to support the athlete's physical and mental well-being and facilitate recovery in both performance and health.

By addressing both physical and psychological aspects, these strategies help athletes regain their energy balance and return to their sport in a healthier, more sustainable way.

RED-S can have a profound impact on both an athlete's performance and long-term health. Early recognition of its signs, taking steps to restore energy balance, and fostering a supportive environment are essential to ensuring both athletic success and overall well-being. With proper management, athletes can return to peak performance while preventing long-term health consequences.

If you are wanting advice on managing RED-S, or have any further questions about this condition, do not hesitate to reach out to us at Physio Inq McMahons Point.

We are here to help!