RED-S Relative Energy Deficiency in Sport for Women and Men

What is RED-S? Assessing the Risk and Treatment through Nutrition

By Rebecca Jaspan, MPH, RD, CDN, CDCES and the LCWNS Team

What is Relative Energy Deficiency in Sport?

Relative Energy Deficiency in Sport, also known as RED-S, refers to impaired physiological functioning caused by energy deficiency.  It includes but is not limited to impairments of metabolic rate, menstrual function, bone health, immunity, protein synthesis, and cardiovascular health.  An athlete diagnosed with RED-S will have low energy availability or insufficient intake to support the level of energy expenditure required for the demands of their sport in addition to supporting the health and function of daily living.  RED-s used to be referred to as the Female Athlete Triad, whose symptoms include low energy availability, menstrual dysfunction, and poor bone health.  In 2014, the International Olympic Committee expanded the clinical model for RED-S to also include males.  This model greatly widens the scope of this condition beyond menstrual function and bone health to include other body systems and psychological health imperative to athletic performance.

Any individual who participates in physical activity is at risk of developing low energy availability and therefore at risk for the consequences of RED-S.  Athletes who are at increased risk typically include runners, cyclists, and climbers.  Additionally, RED-S is commonly seen in sports that involve certain weight requirements such as wrestling or rowing, as well as sports with possible aesthetic pressures such as dance and gymnastics.

Not only is adequate caloric intake a concern, it is also common for these specific individuals to follow strict meal regimens and even eliminate specific foods or food groups they believe to offer a competitive advantage.  This can also lead to an unhealthy obsession with food and body as well as over-training.  If these symptoms are not treated, athletes are at risk of developing eating disorders.  It is estimated that 6 – 45% of female athletes and 0 – 19% of male athletes demonstrate disordered eating patterns.

The RED-S Risk Assessment Model is used to diagnose RED-S.  Upon assessing  the athlete’s presentation and symptoms, he or she is classified into “Green Light” or low risk, “Yellow Light” or moderate risk, and “Red Light” or high risk categories.  These categories help inform sport participation.  At the “Green Light” level, full participation is granted; “Yellow Light” risk allows for sport participation with supervision and a medical treatment plan with regular re-evaluation; at the “Red Light” risk level, sport participation is not granted, as participation would pose a serious health risk and may distract the athlete from devoting the time and attention needed on treatment and recovery from RED-S.

Treatment Options

Treatment for RED-S involves a team of health professionals including a sports medicine doctor, dietitian, athletic trainer, sports psychologist, and sports psychiatrist.  In our practice, the dietitian’s role serves to correct the energy deficiency by increasing energy intake and or decreasing energy output.  The focus is on replenishing glycogen, repairing muscles, ensuring adequate fat storage, improving bone health and decreasing inflammation through adequate nutrition, muscle rest, and using tools to aid in engaging the parasympathetic nervous system..  Many studies show interventions to increase energy availability are successful in reversing impaired functions seen in RED-S.  In one study, female athletes with menstrual dysfunction increased their intake to 40kcal/g of their fat free mass daily resulting in resumed menses in about of 2.6 months.  Keep in mind, bone mineral density must be assessed using a DEXA scan. For more on osteoporosis and bone health, read Osteoporosis and Eating Disorders.

In collaboration with the medical team, LCWNS RD’s work toward nutrition replenishment, resumed and regular menses in females, and both hormone and electrolyte balance with improvement in bone density for males and females. If you notice signs and symptoms such as weight loss, prolonged healing from injuries, decreased endurance and concentration, and irritability, you may be at risk for RED-S and should consult a sports medicine doctor and dietitian.  When addressed early, not only can you prevent further complications, a full recovery from RED-S and return to your sport, whether recreational or competitive, is possible.

Schedule with Rebecca Jaspan, MPH, RD, CDN, CDCED by clicking here


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