Pushing your body in training is part of sport but when exercise, nutrition, and recovery fall out of balance, performance and health can suffer. This condition is known as RED-S (Relative Energy Deficiency in Sport).

Once thought to affect only female athletes under the name Female Athlete Triad, RED-S is now recognised as a condition that can impact all genders, all ages, and all sports. Knowing the red flag signs can help you recognise the problem early and prevent long-term consequences.

What Is RED-S?

RED-S occurs when there’s a chronic mismatch between energy intake (food) and energy expenditure (exercise and daily life). In short: the body doesn’t get enough fuel for its needs.

This energy deficiency doesn’t just affect performance it impacts almost every system in the body, including bone, hormone, cardiovascular, and mental health.

Red Flag Signs You Shouldn’t Ignore

1. Menstrual and Hormonal Changes

Missed or irregular periods
Reduced libido
Signs of low estrogen or testosterone

2. Constant Fatigue

Feeling drained even after rest
Decline in endurance or strength
Slower recovery after training

3. Increased Injuries and Illness

Stress fractures or recurrent injuries
Frequent colds, infections, or slower wound healing

4. Performance Decline

Plateauing or worsening results despite training hard
Feeling weaker or slower without explanation

5. Mood and Cognitive Changes

Irritability, anxiety, or low mood
Difficulty concentrating or “brain fog”

6. Digestive Issues

Bloating, constipation, or stomach discomfort
Loss of appetite

Why Early Recognition Matters

Left unaddressed, RED-S can cause:

Osteoporosis and increased fracture risk
Long-term hormonal imbalance
Fertility challenges
Chronic fatigue and burnout
Serious mental health consequences

👉 The earlier it’s identified, the easier it is to reverse with proper nutrition, recovery, and medical support.

How Physiotherapy and Multidisciplinary Care Help

A women’s health physiotherapist or sports physio can:

Screen for RED-S red flags during assessment
Support safe return-to-training strategies
Address pelvic health changes (like menstrual loss or pelvic pain)
Refer to nutritionists, sports physicians, or psychologists for holistic care

RED-S is not about “not training hard enough”, it’s about the body being under-fuelled and over-stressed. Recognising the red flags early can protect your health, hormones, bones, and long-term performance.

✨ Concerned about fatigue, missed periods, or recurring injuries? Book a consultation with our physiotherapists at Renard Clinic for safe, evidence-based guidance.