What is the appropriate management for a patient with a blood test indicating a diagnosis of Relative Energy Deficiency in Sport (RED-S), likely due to intense athletic training and potential disordered eating or body image issues?

Management of Blood Test Indicating RED-S Diagnosis

When blood tests suggest RED-S, immediately implement a risk-stratified approach using the IOC RED-S Risk Assessment Model, prioritizing restoration of energy availability to ≥45 kcal/kg fat-free mass/day through multidisciplinary care involving a sports physician, sports dietitian, and mental health professional, with sport participation decisions based on severity of laboratory abnormalities, hormonal dysfunction, and cardiovascular findings. 1

Initial Laboratory Assessment and Risk Stratification

The blood test findings must be interpreted within the IOC's three-tier risk framework 1:

High Risk (Red Light - No Sport Participation)

• ECG abnormalities indicating cardiac dysfunction from prolonged energy deficiency 1
• Severe laboratory abnormalities including electrolyte disturbances, particularly in athletes using extreme weight loss techniques 1
• Abnormal hormonal profiles with evidence of physical/psychological complications related to low energy availability 1
• Athletes in this category require immediate medical intervention and complete restriction from training and competition 1

Moderate Risk (Yellow Light - Restricted/Modified Participation)

• Abnormal hormonal profile in men suggesting hypothalamic-pituitary-gonadal axis suppression 1
• Functional hypothalamic amenorrhea >6 months in females 1
• Reduced bone mineral density (Z-score < -1 SD or decline from previous measurement) 1
• Prolonged relative energy deficiency without severe complications 1
• These athletes require close monitoring and modified training while undergoing treatment 1

Low Risk (Green Light - Full Participation)

• Normal hormonal and metabolic function 1
• Healthy bone mineral density as expected for sport, age, and ethnicity 1
• Athletes can continue full participation with preventive monitoring 1

Comprehensive Medical Evaluation Protocol

Beyond the initial blood work, the IOC Return-to-Play Model requires systematic assessment across multiple domains 1:

Step 1: Medical Factors Assessment

• Hormonal evaluation: Document specific abnormalities in reproductive hormones, thyroid function, metabolic markers 1
• Electrolyte panel: Critical for identifying life-threatening imbalances 1
• ECG: Mandatory to rule out cardiac complications from prolonged energy deficiency 1
• DXA scan: Assess bone mineral density and body composition 1
• Menstrual history: Document amenorrhea duration, age at menarche (delayed if >16 years indicates high risk) 1
• Weight history: Identify substantial weight loss (5-10% body mass in 1 month indicates moderate risk) 1
• Psychological screening: Evaluate for depression, anxiety, disordered eating patterns 1

Step 2: Sport-Specific Risk Modifiers

• Type of sport: Weight-sensitive and leanness sports (aesthetic, endurance, weight-class) carry highest risk 1, 2
• Competition level: Elite athletes face greater pressure and risk 1
• Individual vs team dynamics: Consider peer influence and team culture 1

Step 3: Decision Modifiers

• Timing considerations: In-season vs off-season, travel demands, environmental factors 1
• External pressures: Document pressure from coaches, sponsors, family that may compromise treatment adherence 1

Treatment Implementation: The Core Multidisciplinary Team Approach

The Australian Institute of Sport and IOC consensus emphasizes that health must be the priority over performance 1. Treatment requires coordination between three core specialists 1:

Nutritional Intervention (Sports Dietitian-Led)

Primary goal: Achieve energy availability ≥45 kcal/kg fat-free mass/day 2, 3

• Immediate dietary modifications: Increase total energy intake while maintaining adequate macronutrient distribution 1
• Calcium supplementation: Ensure 1500 mg/day through diet or supplements 1
• Vitamin D optimization: Maintain 25(OH)D levels 32-50 ng/mL per Endocrine Society guidelines 1
• Nutritional assessment: Complete diet history, evaluate for restrictive patterns, food allergies/intolerances, and cultural factors affecting food choices 1
• Energy availability calculation: Though difficult to measure precisely in field settings, estimate EA and track trends 1, 4

Critical caveat: Weight should not be the sole focus—athletes may be weight-stable but energy-deficient 1. The sports dietitian must assess psychological components of food choices and body image concerns 1.

Medical Management (Sports Physician-Led)

Hormonal therapy considerations (when nutritional intervention alone is insufficient):

• For females with prolonged amenorrhea and low bone density: Transdermal estradiol 100 μg patch twice weekly plus cyclic micronized progesterone 200 mg for 12 days/month is preferred over combined oral contraceptives for bone protection 2
• Contraindication: Oral contraceptives may mask menstrual dysfunction and are not recommended as first-line treatment 1, 2
• For males: Address testosterone deficiency if present, though evidence is limited 1

Bone health optimization:

• High-impact loading programs: Implement 2-3 days/week for non-weight bearing sports 1
• Resistance training: Essential for athletes with decreased bone mineral density 1
• Monitoring: Repeat DXA scans to track bone density changes 2

Cardiovascular monitoring: Assess for dysfunction related to prolonged energy deficiency 2

Psychological Treatment (Mental Health Professional-Led)

Mandatory when disordered eating or eating disorders are present 1:

• Cognitive behavioral therapy (CBT): First-line intervention for eating problems and body image issues 1
• Dialectical behavior therapy: Alternative for complex cases 1
• Family-based therapy: Particularly important for adolescent athletes 1
• Treatment duration: Typically requires several months 1
• Comorbidity management: Address depression, anxiety, and other psychological problems concurrently 1
• Pharmacotherapy: Antidepressants may be indicated for comorbid conditions 1

Escalation criteria for intensive treatment 1:

• Medical complications requiring inpatient care
• Risk of self-harm
• Lack of progress in outpatient treatment
• Severe eating disorder (anorexia nervosa) requiring residential or partial hospitalization 1

Psychological indicators of problematic low energy availability: Early signs include mood changes, fatigue, psychological conflict; severe outcomes include reduced well-being, elevated anxiety, depressive symptoms 5

Monitoring and Return-to-Play Criteria

Monthly Reassessment Protocol 2

• Menstrual status: Document cycle regularity in females 2
• Weight trends: Monitor for appropriate weight restoration without rapid fluctuations 1
• Hormonal panels: Repeat to assess normalization of metabolic and reproductive function 1, 2
• Performance markers: Track training quality, injury occurrence, illness frequency 1
• Psychological status: Evaluate treatment adherence and mental health progress 1, 5

Clearance for Full Competition 1, 2

Athletes can return to unrestricted sport participation when:

• Laboratory values normalize: Hormones, electrolytes within normal ranges 1
• Menstrual function restores: Regular cycles for females (or appropriate hormonal profile for males) 1, 2
• Bone health stabilizes: No new stress fractures, improving or stable BMD 1, 2
• Energy availability sustained: Consistent EA ≥45 kcal/kg FFM/day 2, 3
• Psychological stability: Treatment compliance, absence of active eating disorder 1
• Cardiovascular function normal: No ECG abnormalities 1, 2

Common Pitfalls and How to Avoid Them

Pitfall 1: Relying Solely on Weight as an Indicator

Solution: Athletes may maintain stable weight while remaining energy-deficient 1. Always calculate energy availability and assess hormonal function regardless of weight 1.

Pitfall 2: Prescribing Oral Contraceptives to "Fix" Amenorrhea

Solution: OCPs mask the problem without addressing underlying energy deficiency and do not provide adequate bone protection 1, 2. Prioritize nutritional restoration first 2.

Pitfall 3: Allowing Athletes to Continue Training Despite Red Light Criteria

Solution: External pressures from coaches, sponsors, and athletes themselves must not override medical safety 1. Document these pressures but maintain restriction when indicated 1.

Pitfall 4: Missing Psychological Components

Solution: Athlete resistance to treatment almost always indicates psychological factors 1. Involve mental health professionals early, especially when athletes deny health consequences while pursuing sport goals 5.

Pitfall 5: Inadequate Follow-Up Duration

Solution: Treatment typically requires several months 1. Establish long-term monitoring protocols rather than expecting rapid resolution 1.

Prevention and Education

The IOC consensus emphasizes prevention through 1:

• Educational programs: Cover RED-S, healthy eating, energy availability risks, and how these affect health and performance 1
• De-emphasize weight: Focus on nutrition and health as performance enhancers rather than body composition targets 1
• Avoid body criticism: Coaches and support staff must refrain from comments about athlete body shape/weight 1
• Promote awareness: Good performance does not equal good health—athletes can perform well while developing serious health problems 1
• Encourage early treatment: Timely intervention prevents progression to severe complications 1

Special Considerations for Adolescent Athletes

Adolescents face unique risks 1:

• Growth and development impairment: LEA affects peak bone mineral density accrual and final height 1
• Neurological development: Brain maturation may be compromised 1
• Reproductive system development: Long-term fertility implications 1
• Higher prevalence: Youth athletes show particularly high rates of RED-S symptoms 6
• Delayed menarche: Primary amenorrhea (no menarche by age 15-16) indicates high risk 1

Management adjustments: More aggressive nutritional intervention, family involvement in treatment, and careful monitoring of growth parameters 1.

1, 2, 6, 5, 3