Beyond the female athlete triad – understanding Relative Energy Deficiency in Sport (RED-S)

In the world of sports, optimising performance and maintaining athlete health is paramount. One critical aspect that has gained attention in recent years is the concept of Relative Energy Deficiency in sport (RED-S) Initially recognised as the ‘Female Athlete Triad’, the understanding of this condition has evolved, highlighting its impact on both male and female athletes and encompassing a broader range of physiological systems. In this blog I’ll outline a few of the many things I learnt from Margo Mountjoy’s Masterclass on RED-S.

If you’d like to learn all about RED-S from expert Margo Mountjoy, watch her full Masterclass HERE.

From Female Athlete Triad to RED-S

The term “Female Athlete Triad” has traditionally been used to describe a syndrome in female athletes characterised by three interrelated components: disordered eating, menstrual dysfunction, and decreased bone mineral density. However, as research progressed in this field, it became clear that this condition was not exclusive to females and involved more than just three systems. Thus, the term RED-S is used to reflect a more comprehensive understanding of the condition.

What is RED-S?

RED-S is defined as a state of impaired physiological functioning caused by exposure to prolonged or severe low energy availability. Low energy availability occurs when the athlete’s energy level does not meet the demands of daily body function and their sport/exercise. Athletes considered to be at high risk of RED-S may include those who compete in aesthetic sports (e.g., gymnastics), long distance runners, or weight-related sports (e.g., lightweight rowing, jockeying). Athletes/active people with disordered eating are commonly associated with a high risk of RED-S, however we must also consider the impact of factors like food insecurity, post-exercise appetite suppression, or even highly busy individuals who lack the time for proper dietary intake during the day. RED-S can affect multiple body systems and lead to various problems, including:

• Impaired menstrual/reproductive function
• Impaired bone health
• Impaired cardiovascular function
• Mental health issues
• Urinary incontinence
• Reduced skeletal muscle function
• Impaired growth and development
• Impaired energy metabolism
• Impaired haemotological function
• Sleep disturbances
• Reduced immunity
• Impaired gastrointestinal function
• Impaired energy metabolism
• Impaired glucose and lipid metabolism
• Impaired neurocognitive function

So, as you can see RED-S includes far more than just a triad of body systems – and, as you can imagine, these impairments can have a serious effect on an athlete’s performance.

Assessing for RED-S

So what are we supposed to do if we suspect somebody to be suffering from RED-S? Unfortunately, there are no diagnostics tests, and as physios we are likely going to be seeing an athlete who is already experiencing musculoskeletal injuries as a result of RED-S, however the International Olympic Committee developed a useful tool called the RED-S Clinical Assessment Tool version 2 (RED-S CAT2) to assist clinicians with screening and assessing for RED-S in patients. The RED-S CAT2 is a three step tool, the first step involves patient screening through population-specific questionnaires and the clinical interview. The second step is a RED-S severity/risk assessment, and the third step includes seeking a clinical diagnosis (and subsequent treatment) for RED-S from a physician. Watch the below snippet from Margo’s Masterclass in which she explains a range of factors to consider when assessing a patient for low energy availability:

What is the role of the physio?

A physiotherapist’s role is crucial in a multidisciplinary approach to preventing and treating RED-S, as well as mitigating further health and performance effects. As primary care providers, physiotherapists can play a significant role in:

• Initial screening: Early identification and appropriate referral for RED-S.
• Rehabilitation: Managing bone stress injuries and optimising athlete load.
• Incorporating strength and resistance training: Particularly for non-weight bearing athletes, such as swimmers.

Watch the below video from Margo’s Masterclass where she outlines athlete-specific ways to treat low energy availability:

While physiotherapists are not dietitians, having a basic understanding of sports nutrition is essential to provide the correct education. This knowledge aids in addressing the nutritional needs critical for bone health and overall energy availability. Margo Mountjoy explains the importance of prioritising bone-building nutrients in the below snippet from her Masterclass:

Wrapping up

Relative Energy Deficiency in Sport is a multifaceted condition affecting athletes’ physical and psychological health. As physiotherapists, understanding RED-S and its broader implications is vital for providing comprehensive care to athletes and highly active people. By understanding at-risk populations, recognising the signs and symptoms, collaborating with a multidisciplinary team, and implementing effective management strategies, we can help athletes achieve their full potential while safeguarding their long-term health. Educating athletes and their support networks about the importance of energy balance and overall well-being is key to preventing and managing RED-S effectively.

For a comprehensive understanding of RED-S and its implications in the sporting setting – watch Margo Mountjoy’s full Masterclass HERE.