Understanding the Root Cause: Low Energy Availability
Relative Energy Deficiency in Sport (RED-S) is a syndrome that stems from a state of low energy availability (LEA). This means an athlete's energy intake is consistently insufficient to support the high demands of their daily exercise and regular bodily functions. While it was once known as the 'Female Athlete Triad' (disordered eating, menstrual dysfunction, and bone loss), the term was updated to RED-S to reflect that it affects both male and female athletes across multiple physiological systems. The syndrome can develop unintentionally due to underestimating nutritional needs or intentionally through restrictive eating patterns.
Physical Symptoms of RED-S
One of the first steps in learning how to tell if you have RED-S is recognizing the many physical symptoms. Because the body is in a state of energy conservation, it prioritizes essential life-sustaining functions and impairs others, leading to a cascade of negative health consequences.
Common physical signs include:
- Chronic Fatigue: Persistent tiredness and low energy levels are hallmarks of RED-S and go beyond typical training soreness.
- Frequent Illness: A compromised immune system, which is common with RED-S, leads to more frequent colds, flu, and other infections that take longer to recover from.
- Recurrent Injuries: An inability to adequately repair tissues increases the risk of bone stress injuries, such as stress fractures, and delays the healing of soft tissue injuries.
- Gastrointestinal Issues: Bloating, constipation, and other digestive problems can become common due to altered gut function.
- Decreased Performance: Noticeable declines in athletic performance, such as reduced endurance and strength, despite persistent training efforts.
- Hair Loss: The body redirects energy from non-essential functions, which can lead to thinning hair.
- Cold Intolerance: Feeling constantly cold, even in moderate temperatures, due to a lower metabolic rate.
Psychological and Hormonal Indicators
The effects of RED-S extend beyond physical manifestations, impacting mental health and hormonal balance significantly. These signs are often overlooked but are critical indicators of the condition.
Key psychological and hormonal symptoms:
- Mood Changes: Irritability, depression, and anxiety are common due to hormonal imbalances and psychological stress.
- Impaired Concentration: Difficulty focusing or 'brain fog' can affect performance and daily life.
- Loss of Libido: A decrease in sexual desire is a sign of hormonal disruption in both men and women.
- Disordered Eating: Developing a difficult relationship with food, including food anxiety or a drive for thinness, is a significant risk factor.
- Menstrual Irregularities: For females, missed or irregular periods (amenorrhea) are a key sign, though oral contraceptives can mask this symptom.
Comparison Table: RED-S vs. Overtraining Syndrome
Distinguishing between RED-S and Overtraining Syndrome (OTS) can be challenging as many symptoms overlap. The table below highlights key differences that can aid in identifying the underlying cause.
| Feature | Relative Energy Deficiency in Sport (RED-S) | Overtraining Syndrome (OTS) |
|---|---|---|
| Root Cause | Inadequate energy intake relative to energy expenditure (Low Energy Availability). | Excessive training volume or intensity without sufficient recovery. |
| Athletic Response | Initial short-term performance gains, followed by a significant, long-term decline. | Protracted decrease in performance, typically following a period of high-intensity training. |
| Primary Marker | Systemic energy deficit affecting multiple body systems (metabolic, hormonal). | Imbalance of training stress and recovery capacity, primarily affecting the neuromuscular system. |
| Injury Type | Increased risk of bone stress injuries (e.g., stress fractures). | Increased risk of muscle and soft tissue injuries. |
| Hormonal Impact | Significant hormonal disruption (e.g., low estrogen/testosterone, high cortisol). | Altered cortisol and catecholamine levels; can overlap with RED-S. |
| Metabolic Rate | Decreased resting metabolic rate as the body conserves energy. | Elevated resting heart rate in severe cases. |
| Psychological | Stronger association with body image and eating anxieties. | Primarily linked to physical and mental exhaustion; can develop into RED-S. |
The Diagnostic Process and Next Steps
If you recognize multiple symptoms, the first and most important step is to consult a healthcare professional experienced in sports medicine. The diagnostic process for RED-S often involves a multidisciplinary team to assess the full picture of your health.
A proper evaluation may include:
- Comprehensive Medical History: A doctor will discuss training routines, eating habits, injury history, and mood to identify patterns associated with RED-S.
- Physical Examination: This includes checking vital signs like heart rate and blood pressure, along with measuring height and weight.
- Blood Tests: Analyzing hormone levels (e.g., estrogen, testosterone) and other markers like ferritin (iron) can confirm systemic changes.
- Bone Density Scans: A DEXA scan may be used to assess bone mineral density, especially in females with menstrual irregularities, to check for osteoporosis or osteopenia.
- Multidisciplinary Team: Treatment typically involves a physician, a registered dietitian, and a mental health professional to address all aspects of the condition, from energy balance to psychological factors.
Conclusion
Knowing how to tell if you have RED-S can be a life-changing step towards regaining your health and athletic potential. The syndrome's widespread effects on multiple body systems mean that early recognition is critical to preventing long-term consequences. Symptoms like chronic fatigue, recurrent injuries, and mood changes are not simply part of being an athlete; they are warning signs that your body needs more energy. By seeking a comprehensive medical evaluation and working with a qualified healthcare team, you can address the root cause of low energy availability and get back on the path to sustained health and performance.
For more information on the official guidelines, consider reviewing the International Olympic Committee's (IOC) consensus statement on RED-S: IOC Consensus Statement on Relative Energy Deficiency in Sport (RED-S): 2018 Update.
