Relative Energy Deficiency in Sport (RED-S)

Relative Energy Deficiency in Sport (RED-S)
Prepared by  Prepared by: Christine May, Senior Research Consultant, Clearinghouse for Sport, Sport Australia (formerly Australian Sports Commission)
evaluated by  Evaluation by: AIS Sports Nutrition, Australian Institute of Sport, Sport Australia (formerly Australian Sports Commission) (August 2017)
Reviewed by  Reviewed by network: Australian Sport Information Network (AUSPIN)
Last updated  Last updated: 18 April 2019
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Relative Energy Deficiency in Sport (RED-S), is a syndrome which can adversely affect the health and performance of athletes. It exists when there is a negative balance between dietary energy intake and the energy expenditure required to support optimal health, daily living activities, growth, and sport.     

Although much of the research and literature relating to RED-S has been an outgrowth from studies of the 'Female Athlete Triad', it is important to note that the condition can affect men and women, able-bodied and disabled populations, and individuals of various races.

Athletes, parents, coaches, and medical practitioners need to understand the signs, symptoms, and dangers of RED-S in order to identify athletes who are in danger of developing, or already have, the syndrome and to determine an appropriate treatment. 

Key Messages 


RED-S may affect men or women. It is most prevalent in sports/activities where leanness/weight are important for performance; aesthetics/appearance; or to meet a weight category.


RED-S is caused by low energy availability and can have long-term health impacts for both women and men.


Diagnosis and treatment of RED-S should be completed by a team of medical specialists.

The Female Athlete Triad (Triad) was first defined in 1992. Initially, in order to be diagnosed, female athletes had to have all three components - an eating disorder, amenorrhea, and osteoporosis. In 2007 the definition was modified to a spectrum disorder (i.e. not all components needed to be present for diagnosis) and the components were broadened to include low energy availability (with or without disordered eating), menstrual dysfunction, and low bone mineral density [source: Elizabeth Matzkin, Emily J. Curry, and Kaitlyn Whitlock, Female Athlete Triad: Past, Present, and Future (PDF - 349KB), Journal of the American Academy of Orthopaedic Surgeons, Volume 23 (7), (July 2015)].

In 2014 the International Olympic Committee (IOC) convened an expert panel to update the 2005 IOC Consensus Statement on the Female Athlete Triad (PDF  - 114 KB). The group determined that scientific evidence and clinical experience indicated that the underlying cause of the Triad was inadequate energy to support optimal physiological health and performance. Additionally, they concluded that low energy availability could affect groups which had previously not been extensively studied such as: men, disabled populations, and athletes of non-Caucasian ethnicity. Taking these factors into account a broader, and more comprehensive, definition was indicated, RED-S:

The syndrome of RED-S refers to impaired physiological function including, but not limited to, metabolic rate, menstrual function, bone health, immunity, protein synthesis, cardiovascular health caused by relative energy deficiency.Beyond the Female Athlete Triad—Relative Energy Deficiency in Sport (RED-S). Margo Mountjoy, British Journal of Sports Medicine, Volume 48 (7), (2014), pp.491-497.

Although this change in the definition/scope of the Triad has been generally accepted by the sports medicine fraternity, some groups, including the Female Athlete Triad Coalition, have argued that the new term is not sufficiently supported by scientific evidence (unlike the Triad) to be adopted at this time. 

In the simplest terms the underlying cause of RED-S is low energy availability (EA). That is the amount of dietary energy remaining for the body to function properly after exercise training expenditure. This is often expressed as an equation:

Energy available (EA) = Energy intake (EI) - Exercise Energy Expenditure (EEE) / fat-free mass (FFM) 

Causes of low energy availability

Although it is often associated with disordered eating or an eating disorder low energy availability can also be caused inadvertently or by mismanaging weight control efforts. Examples of this can include: 

  • Changes to training/competition load, including short turnarounds between training sessions and/or competitions (i.e. increasing EEE above EI).
  • Lack of skills, time, and/or money for meal planning and preparation. 
  • Not understanding individual energy needs for sport. 

More serious disordered eating which may lead to, or be caused by, an eating disorder may include dieting or the use of fasting, diet pills, laxatives, diuretics etc. 

Coaches who observe such signs should refer their athlete to a medical professional for diagnosis and treatment.

More information about athlete eating disorders as a mental health concern can be found in the Clearinghouse for Sport topic, Sport & Mental Health

RED-S exists on a continuum from optimal energy availability and physiological health to low energy availability (with or without an eating disorder) severely impacting on physiological health (i.e. menstrual dysfunction, bone health etc.). The 2014 IOC Consensus statement provided a simplified diagram of the various health consequences of RED-S, which range from metabolic, to immunological, cardiovascular, and psychological: 

Additionally, the potential performance effects can include: increased injury risks and decreased performance and training responses, as well as mood changes, depression, and irritability. 

RED-S is most common in sports where leanness and/or weight are important for performance (long distance running, road cycling); aesthetics/appearance (gymnastics, dancing); or to meet a weight category (wrestling, boxing, combat sports).   

Screening for RED-S can be difficult as the symptoms can be quite subtle. It is important for parents/family, coaches, and medical practitioners to be aware of the potential issue in order to detect it early and refer the athlete to appropriate healthcare providers. As the primary cause of RED-S is energy deficiency some early signs can be: 

  • Disordered Eating (DE) or an Eating Disorder (ED);
  • weight loss;
  • lack of normal growth and development; 
  • menstrual dysfunction; 
  • recurrent injuries and illnesses; 
  • decreased performance; or 
  • mood or social behavioural changes.

Coaches, parents or others who observe such signs should refer their athlete to a medical professional for diagnosis and treatment.

RED-S Clinical Assessment Tool (RED-S CAT)

The RED-S Clinical Assessment Tool (RED-S CAT) has been developed by the IOC working group as a tool to help sports medicine professionals with the practical screening and management of RED-S athletes. The tool is modelled after the Sport Concussion Assessment Tool (SCAT-3) which has been successfully used in clinical practice.

The RED-S Risk Assessment and Return to Play (RTP) models use a Red Light (high risk) – Yellow Light (caution) – Green Light (low risk) scale to help evaluate athletes/active individuals suspected of having relative energy deficiency and for guiding return to play decisions. The model is flexible enough to allow sports medicine professionals to apply their knowledge of sport-specific demands and individual characteristics to the decision making paradigm. 

Before an athlete who has been treated for RED-S returns to sport/physical activity it is important to assess both their current health and the physical requirements of their sport. 

Athletes assessed in the Red (high risk) category should not participate in sport due to the potential risk to their health and the need to focus on recovery. Yellow (moderate risk) athletes may continue to train as long as they are following a treatment plan and may be cleared to compete under supervision of a medical team. Green (low risk) categorisation means that full sport participation is ok.  


Treatment for RED-S, and in particular for the underlying low Energy Availability (EA) will generally involve increasing Energy Intake (EI) potentially in combination with reducing exercise. As there are not currently any standardised guidelines to determine EA, and measurement of both EI and exercise expenditure are frequently imprecise, it can be difficulty to accurately determine optimal conditions for individual EA. 

The IOC working group therefore recommended a practical approach of increasing current EI by ∼300–600 kcal/day and addressing suboptimal practices related to energy spread over the day and around exercise sessions, dietary composition, and food-related stress [source: Mountjoy M, Sundgot-Borgen J, Burke L,, The IOC consensus statement: beyond the Female Athlete Triad—Relative Energy Deficiency in Sport (RED-S), British Journal of Sports Medicine, Volume 48(7), (2014), pp.491-497].

Additional treatment may be required to address menstrual dysfunction for women, optimise bone health, and for any psychological conditions which may exist or develop.

It is recommended that treatment and monitoring plans involve a qualified sports medicine practitioner with support from a multi-disciplinary team as required.

The following tools were provided by Sue Robson from Sport Scotland:

Case Studies for the female athlete triad:

Where possible, direct links to full-text and online resources are provided. However, where links are not available, you may be able to access documents directly by searching our licenced full-text databases (note: user access restrictions apply). Alternatively, you can ask your institutional, university, or local library for assistance—or purchase documents directly from the publisher. You may also find the information you’re seeking by searching Google Scholar.


  • The Active Female: Health Issues Throughout the Lifespan (Second Edition), McComb J, Norman R and Zumwalt M (Editors), Springer (2014). This book contains information intended to increase the awareness of wellness and fitness issues for active females and their family members. An overview of the Female Athlete Triad is presented in Part II.
  • The Female Athlete Triad, Gordon C and LeBoff M (Editors), Springer (2014). This book focuses solely on the female athlete triad - its origins, its recognition, and most importantly, its management. Each chapter includes suggestions on how to educate and communicate with young athletes and their parents, as well as trainers and coaches, on how to manage the illness outside of the direct clinical setting. 

Fact Sheets



  • An evidence-based approach to Relative Energy Deficit in Sport (RED-S) (PDF  - 2.1MB). Jennifer M. Doane, conference presentation, EATA Annual Meeting & Clinical Symposium, (8 January 2016). Provides an overview of the Female Athlete Triad vs RED-S and explains the impact of starvation diets on athletes. Identifies current best-practice for evaluating athletes suspected of RED-S and instituting evidence-based decision making for treatment and return-to-play.
  • Eating disorders in female athletes: use of screening tools. Knapp J, Aerni G and Anderson J, Current Sports Medicine Reports, Volume 13, Number 4 (2014). Eating disorders are more prevalent in the female athlete population than in the general population and carry short-term and long-term consequences that can affect sport performance. There are several screening tools available that have been studied in the general population, but fewer tools have been validated specifically in female athletes. The authors discuss various screening tools available and the evidence for each one. Screening for eating disorders in all female athletes is an important part of the preparticipation examination and should be done using a tool specifically validated for the female athlete.
  • The Female Athlete Triad: clinical report. Amanda K. Weiss Kelly, Suzanne Hecht, Pediatrics, (July 2016). This report outlines the current state of knowledge on the epidemiology, diagnosis, and treatment of the triad conditions.
  • Female Athlete Triad and its components: Toward improved screening and management. Javed A, Tebben P, Fischer P and Lteif A, Mayo Clinic Proceedings, Volume 88, Issue 9 (2013). This article provides a comprehensive review of literature regarding current definitions of the triad components, epidemiology, pathophysiology, and recommended screening and management guidelines. Low energy availability, from either dietary restriction or increased expenditure, plays a pivotal role in development of the triad. Athletes involved in “lean sports” (those that emphasize weight categories or aesthetics, such as ballet, gymnastics, or endurance running) are at highest risk. Treatment is centred on restoring energy availability to reverse adverse changes in the metabolic milieu. Prevention and early recognition of triad disorders are crucial to ensure timely intervention. Caregivers and physicians of female athletes must remain vigilant in education, recognition, and treatment of athletes at risk.
  • The Female Athlete Triad: Components, nutrition issues, and health consequences (PDF  - 170 KB), Manore M, Kam L and Loucks A, Journal of Sports Sciences, Supplement 1, Volume 25, p61 (2007). This paper, which was part of the International Association of Athletics Federations (IAAF) 2007 Nutritional Consensus Conference, briefly reviews the components of the Female Athlete Triad, energy availability, menstrual status and bone health.
  • The Female Athlete Triad: What's a doctor to do? Lebrun C, Current Sports Medicine Reports (American College of Sports Medicine), Volume 6, Issue 6, p397 (2007). Sports medicine physicians often encounter athletes with at least one component of the Female Athlete Triad—disordered eating, menstrual dysfunction, and altered bone mineral density. Recognizing these conditions early is critical because prolonged exposure can lead to serious, potentially irreversible, health consequences. This review focuses on the newer scientific findings in this important area of women's health. There remains a distinct lack of prospective epidemiologic data assessing prevalence and causes, and outcome studies on the efficacy of prevention and treatment of the Triad disorders. Nevertheless, the underlying message remains that participation in sports and physical activity benefits the long-term health of girls and women, and should be encouraged.
  • Long term consequences of the female athlete triad. Thein-Nissenbaum J, Maturitas, Volume 75, Issue 2 (2013). Triad symptoms are distributed along a spectrum between optimal health and disease; all of the components of the triad may not be affected simultaneously. Women of all ages should be assessed for triad components during routine annual physical examinations; appropriate measures to treat any current triad components should be implemented. In addition, women in their 30s, 40s and early 50s should be screened for a history of the female athlete triad. Multidisciplinary management of these conditions is strongly recommended.
  • Low Energy Availability in Exercising Women: Historical Perspectives and Future Directions. Joanne Slater, Rachel Brown, Rebecca McLay-Cooke, Katherine Black, Sports Medicine, Volume 47 (2), (February 2017), pp.207–220. Research on the health of female athletes has developed substantially over the past 50 years. This review aims to provide an overview of this research and identify directions for future work. Also discusses the need for further research into LEA in male athletes and junior and emerging athletes; and the need for the development of a standardised tool to diagnose LEA.
  • Negative Consequences of Low Energy Availability in Natural Male Bodybuilding: A Review. Petter Fagerberg, Sport Nutrition & Exercise Metabolism, (published online 7 May 2017). Since no well-controlled studies have been conducted in natural male bodybuilders on effects of LEA, the aim of this review was to summarize what can be extrapolated from previous relevant research findings in which EA can be calculated. The reviewed literature indicates that a prolonged EA<25kcal/kgFFM results in muscle loss, hormonal imbalances, psychological problems, and negatively affects the cardiovascular system when approaching the lower limits of body fat (~4-5%) among males. Case-studies on natural male bodybuilders who prepare for contest show muscle loss (>40% of total weight loss) with EA<20kcal/kgFFM, and in the study with the lowest observed body fat (~4kg) major mood disturbance and hormonal imbalances co-occurred.
  • Nutritional Consequences And Treatment Of Relative Energy Deficiency In Sport RED-S. (PDF  - 616KB) Jessica Laroche, US Speedskating Dietician, conference presentation, Female Athlete Injury conference, (2015?). Provides information on distinguishing between Female Athlete Triad and RED-S; defining energy availability; screening for RED-S; nutritional treatment (Triad vs RED-S guidelines); return to play models; and prevention.
  • Obstacles in the Optimization of Bone Health Outcomes in the Female Athlete Triad (PDF  - 229 KB), Ducher G, Turner A, Kuku!an S, Pantano K, Carlson J, Williams N and De Souza M, Sports Medicine, Volume 41 Issue 7, p587 (2011). Maintaining low body weight for the sake of performance and aesthetic purposes is a common feature among young girls and women who exercise on a regular basis, including elite athletes. High energy expenditure without adequate compensation in energy intake leads to an energy deficiency, which may ultimately affect reproductive function and bone health. The combination of low energy availability, menstrual disturbances and low bone mineral density is referred to as the ‘female athlete triad’. This review investigates current issues, controversies and strategies in the clinical management of bone health concerns related to the female athlete triad.
  • Optimal health: including female athletes! Part 1 Bones. Dr Nicky Keay, BJSM blog, (26 March 2017). Part 1 of the blog mini-series on RED-S.
  • Optimal health: including male athletes! Dr Nicky Keay, blog post, (9 January 2017). Part 2 of the blog mini-series on RED-S.
  • Optimal health: especially young athletes! Part 3 Consequences of Relative Energy Deficiency in sports. Dr Nicky Keay, blog post, (13 January 2017). Part 3 of the blog mini-series on RED-S.
  • Optimal Health: For All Athletes! Part 4 – Mechanisms. Dr Nicky Keay, British Association of Sport & Exercise Medicine (BAsem), (13 April 2017). Part 4 of the blog mini-series on RED-S.
  • Parallels with the Female Athlete Triad in male athletes, Tenforde A, Barrack M, Nattiv A, Fredericson M, Sports Medicine, Volume 46, Issue 2, p171-182 (2015). Subsets of both female and male athletes are at increased risk of impaired bone health and bone stress injuries. The Female Athlete Triad (Triad) is defined as the interrelationship of low energy availability (with or without disordered eating), menstrual dysfunction, and low bone mineral density. The Triad may result in health consequences, including bone stress injuries. This review presents evidence that an analogous process may occur in male athletes. A review of the available literature indicates that a subset of male athletes may experience adverse health issues that parallel those associated with the Triad, including low energy availability (with or without disordered eating), hypogonadotropic hypogonadism, and low bone mineral density. Consequently, some male athletes may be predisposed to developing bone stress injuries, and these injuries can be the first presenting feature of associated Triad conditions. The authors discuss the evidence for impaired nutrition, hormonal dysfunction, and low bone mineral density in a subset of male athletes, and how these health issues may parallel those of the Triad.
  • Raw And Real: RED-S. Katie Schofield, blog post, (14 September 2014). Provides a personal story of an educated (degree in nutrition) elite athlete when she was diagnosed with RED-S, what it was like for her, and a good plain language overview of the signs, symptoms, and potential dangers of RED-S.
  • Relative energy deficiency in sport. Margo Mountjoy, Aspetar Sports Medicine Journal, Volume 4, (October 2015). Provides an overview of RED-S, the health and performance implications, RED-S in male athletes as well screening, treatment and return to play considerations. Additionally, there is information specific to aquatic sport athletes.
  • Should you suspect the female athlete triad? Payne J and Kirchner J, The Journal of Family Practice, Volume 63, Number 4 (2014). Previously, the triad was described as disordered eating, amenorrhea (having no menstruation for more than three sequential months), and osteoporosis. However, this definition has been expanded to encourage detection before clinical problems progress. In most instances, an athlete will develop only one or 2 of the 3 components of the triad. This article describes the clinical manifestations of the triad, how to screen patients for it, and indications for referring affected athletes.
  • Sport Performance and Relative Energy Deficiency in Sport. Dr Nicky Keay, blog post, (11 March 2017). Post looks at the ‘holy grail’ of training to improve performance and achieve goals and explains that for athletes diagnosed with RED-S, due to a mismatch of energy intake and expenditure, any attempt at increase in training load will not produce the expected adaptations and improvement in performance. Nutritional supplements will not fix the underlying problem. Nor will treatments for recurrent injuries. If the underlying cause of drop in performance or recurrent injury is RED-S, then tackling the fundamental cause is the only long term solution for both health and sport performance.
  • What is relative energy deficiency in sport (RED-S)? Katherine Schaumberg, UNC Center of Excellence for Eating Disorders, (6 April 2017). This blog post provides a quick overview of RED-S and techniques for determining if athletes are getting adequate food relative to their exercise output.


  • Associations between the female athlete triad and injury among high school runners. Rauh M, Barrack M and Nichols J, International Journal of Sports Physical Therapy, Volume 9, Number 7 (2014). The purpose of this study was to determine the associations between Triad and risk of lower extremity musculoskeletal injury among adolescent runners.  Eighty-nine female athletes competing in interscholastic cross-country and track were followed, prospectively. It was concluded that  oligo/amenorrhea and low bone mineral density were associated with musculoskeletal injuries among the female interscholastic cross-country and track runners.
  • Body mass related predictors of the Female Athlete Triad among adolescent athletes, Thralls K, Nichols J, Barrack M, Kern M and Rauh M, International Journal of Sport Nutrition & Exercise Metabolism, Volume 26, Issue 1 (2016). Early detection of the female athlete triad is essential for the long-term health of adolescent female athletes. The purpose of this study was to assess relationships between common anthropometric markers and triad components. A sample of 320 adolescent female athletes (mean age 15.9± 1.2 years) was compared to a control group. All underweight categories for the anthropometric measures predicted greater likelihood of menstrual dysfunction and low bone mineral density. This study indicates that low age-adjusted body mass index and ideal body weight may serve as evidence-based clinical indicators that may be practically evaluated in the field. These measures should be tested for their ability as tools to minimize the risk for the triad.
  • Energy availability and the female athlete triad in elite endurance athletes, Melin A,, Scandinavian Journal of Medicine & Science in Sports, Volume 25, Issue 5 (2015). The female athlete triad links low energy availability (EA), with menstrual dysfunction (MD), and impaired bone health. This study examined associations between EA, MD, energy metabolism and the prevalence of Triad-associated conditions in endurance athletes. Forty women age 26.2 ± 5.5 years, body mass index (BMI) 20.6 ± 2.0 kg/m2, body fat 20.0 ± 3.0%, exercising 11.4 ± 4.5 hours/week, were recruited from national teams and competitive clubs. Subjects with low or reduced EA (< 45 kcal/kg FFM/day) had lower resting metabolic rate (RMR) compared with those with optimal EA, as did subjects with MD compared with eumenorrheic subjects. 63% had low/reduced EA, 25% ED, 60% MD, 45% impaired bone health, and 23% had all three Triad conditions. 53% had low RMR, 25% hypercholesterolemia, and 38% hypoglycemia. This study concluded that athletes with low/reduced EA and/or MD had lowered RMR. Triad-associated conditions were common in this group of athletes, despite a normal BMI range. The high prevalence of ED, MD, and impaired bone health emphasises the importance of prevention, early detection, and treatment of energy deficiency.
  • Energy Availability in Athletics: Health, Performance, and Physique, Anna K. Melin, Ida A. Heikura, Adam Tenforde, Margo Mountjoy, Sport Nutrition and Exercise Metabolism, Volume 29(2), pp. 152-164, (March 2019). The reported prevalence of low energy availability (LEA) in female and male track and field athletes is between 18% and 58% with the highest prevalence among athletes in endurance and jump events. In male athletes, LEA may result in reduced testosterone levels and libido along with impaired training capacity. In female track and field athletes, functional hypothalamic amenorrhea as consequence of LEA has been reported among 60% of elite middle- and long-distance athletes and 23% among elite sprinters. Health concerns with functional hypothalamic amenorrhea include impaired bone health, elevated risk for bone stress injury, and cardiovascular disease. Furthermore, LEA negatively affects recovery, muscle mass, neuromuscular function, and increases the risk of injuries and illness that may affect performance negatively. LEA in track and field athletes may occur due to intentional alterations in body mass or body composition, appetite changes, time constraints, or disordered eating behavior. Long-term LEA causes metabolic and physiological adaptations to prevent further weight loss, and athletes may therefore be weight stable yet have impaired physiological function secondary to LEA. Achieving or maintaining a lower body mass or fat levels through long-term LEA may therefore result in impaired health and performance as proposed in the Relative Energy Deficiency in Sport model. Preventive educational programs and screening to identify athletes with LEA are important for early intervention to prevent long-term secondary health consequences. Treatment for athletes is primarily to increase energy availability and often requires a team approach including a sport physician, sports dietitian, physiologist, and psychologist.
  • Energy Deficiency, Menstrual Disturbances, and Low Bone Mass: What Do Exercising Australian Women Know About the Female Athlete Triad? (PDF  - 355 KB), Miller S, Kukuljan S, Turner A, van der Pligt P and Ducher G, International Journal of Sport Nutrition and Exercise Metabolism, Volume 22 (2012). A total of 191 female exercisers, age 18–40 years, engaging in more than 2 hours/week of strenuous activity, completed a survey. Only 10% of respondents could name the 3 components of the female athlete triad. Regardless of reported history of stress fracture, 45% of the respondents did not think that amenorrhea (absence of menses for ≥ 3 months) could affect bone health, and 22% of those involved in lean-build sports would do nothing if experiencing amenorrhea (vs. 3.2% in non-lean-build sports, p  = .005). Lean-build sports, history of amenorrhea, and history of stress fracture were all significantly associated with not taking action in the presence of amenorrhea (all p < .005). Few active Australian women are aware of the detrimental effects of menstrual dysfunction on bone health. Education programs are needed to prevent the female athlete triad and ensure that appropriate actions are taken by athletes when experiencing amenorrhea.
  • Female Recreational Exercisers at Risk for Low Energy Availability. Joanne Slater, Rebecca McLay-Cooke, Rachel Brown, and Katherine Black, Sport Nutrition & Exercise Metabolism, Volume 26 (5), (October 2016), pp.421-427. One-hundred and nine female recreational exercisers, with a mean age of 23.8 (SD 6.9) years were recruited via gyms and fitness centers throughout NZ. Participants completed an online questionnaire including questions from the LEAF-Q (Low Energy Availability in Females Questionnaire). A total of 45.0% (CI, 35.4%, 54.8%) of participants were classified as “at risk“ of LEA. For every extra hour of exercise per week the odds of being at risk of LEA were 1.13 times greater (CI 1.02, 1.25, p = .016). All participants reporting previous stress fracture injuries (n = 4) were classified as at risk for LEA. Significantly more subjects participating in an individual sport were classified as at risk for LEA (69.6%, CI 24.3%, 54.8%) compared with team sports (34.8%, CI 18.7%, 40.5%) (p = .006). The high prevalence of female recreational exercisers at risk of LEA is of concern, emphasizing the importance of increasing awareness of the issue, and promoting prevention and early detection strategies, so treatment can be implemented before health is severely compromised.
  • Higher incidence of bone stress injuries with increasing Female Athlete Triad – Related risk factors: A prospective multisite study of exercising girls and women, Barrack M, Gibbs J, De Souza M, Williams N, Nichols J, Rauh M and Nattiv A, The American Journal of Sports Medicine, Volume 42, Number 4 (2014). This study evaluated the effect of single or combined risk factors as defined by the female athlete triad—a syndrome involving interrelated spectrums consisting of energy availability, menstrual function, and bone mass—with the incidence of BSIs in a multicenter prospective sample of 4 cohorts of physically active girls and women.
  • Low energy availability assessed by a sport-specific questionnaire and clinical interview indicative of bone health, endocrine profile and cycling performance in competitive male cyclists, Nicola Keay, Gavin Francis, Karen Hind, BMJ Open Sport & Exercise Medicine, Volume 4(1), (2018). Fifty competitive male road cyclists were recruited through links of participants in a pilot study, were assessed by a newly developed sport-specific questionnaire and clinical interview (SEAQ-I) and received dual energy X-ray absorptiometry (DXA) bone mineral density (BMD) and body composition scans and blood tests for endocrine markers. Low EA, as assessed using the SEAQ-I, was observed in 28% of cyclists. Low lumbar spine BMD was found in 44% of cyclists. Overall cyclists with low EA, particularly in the long-term, displayed adverse quantifiable measures of bone, endocrinology and performance consequences of RED-S. This study demonstrates that a SEAQ-I is effective for identifying male road cyclists with acute intermittent and chronic sustained low EA.
  • Low energy availability in females: A sleeping giant, Lundy B, Burke L, Vlahovich N, Welvaert M, Hughes D, Waddington G and Drewa M, Journal of Science and Medicine in Sport, Volume 20, Supplement 1 (2017). Low energy availability can occur when an athlete restricts their energy intake and/or increases the volume or intensity of training, with the consequence that there is no longer sufficient energy to fulfil the functions needed to stay healthy. While the previous focus on low energy availability targeted menstrual function and bone health, there is now evidence that the consequences are wider ranging. This study suggests that female athletes who present with illness should be screened for low energy availability. Assistance to better match nutrition and training may improve resilience against illness as well as other aspects of health and performance.
  • Low Energy Availability in New Zealand Recreational Athletes [master’s thesis]. Joanne Slater, University of Otago (2015). This study provides important information on the prevalence and predictors of LEA in New Zealand athletes. Considering the high prevalence of New Zealand recreational athletes at risk of LEA this emphasises the importance of prevention and early detection, so treatment can be implemented before health and performance is severely compromised. Some key findings include: a total of 33.5% (95% CI 26.5%,41.2%) of participants were classified as at risk of LEA. Females had approximately 5.4 times greater probability of being at risk of LEA when compared to males (p<0.001). The dose response relationship between training volume (hours per week) and risk of LEA was found to be significant among female athletes but not males. Further, the majority of participants (males 87.5%, 95% CI, 47.3%, 99.7%, n=7, females, 89.8%, 95% CI 77.8%, 96.6%, n=44) who were classified as at risk of LEA were considered not at risk of an eating disorder.
  • Low-energy density and high fiber intake are dietary concerns in female endurance athletes. Melin, A., Tornberg, Å. B., Skouby, S., Møller, S. S., Faber, J., Sundgot-Borgen, J. and Sjödin, A. Scandinavian Journal of Medicine & Science in Sports, Volume 26, (2016), pp.1060–1071. Low or reduced energy availability (LEA) is linked to functional hypothalamic oligomenorrhea/amenorrhea (FHA), which is frequently reported in weight-sensitive sports. This makes LEA a major nutritional concern for female athletes. The aim of this study was to describe dietary characteristics of athletes with LEA and/or FHA. The authors conclude that low ED together with high fiber content may constitute targets for dietary intervention in order to prevent and treat LEA and FHA in female athletes.
  • Prevalence of illness, poor mental health and sleep quality and low energy availability prior to the 2016 Summer Olympic Games, Drew M, Vlahovich N, Hughes D, et al, British Journal of Sports Medicine, (published online 22 October 2017). All participants reported at least one illness symptom in the previous month. Low energy availability was a leading variable associated with illness in Olympic-class athletes. The estimates duration of symptoms ranged from 2 to 7 days. Factor analyses show the interdependence of various health domains and support multidisciplinary care.
  • Prevalence of Relative Energy Deficiency in Sport among well-trained male Norwegian cyclists and long-distance runners [master’s thesis]. Thomas Birkedal Stenqvist, University of Agder, (2016). The aim of this study was to investigate the prevalence of RED-S and associated health consequences in well-trained male endurance athletes A high prevalence of reduced EA accompanied by metabolic alterations was found in this group of well-trained athletes. However, no differences were observed between EA groups in anthropometric, hormonal biomarkers, blood glucose, blood lipids, or BMD. This may indicate that well-trained male endurance athletes are better protected against associations to negative health consequences in combination with reduced EA, compared to female endurance athletes. 

Other Videos

  • Katie Schofield Interview: Goal setting, dealing with disappointment and RED-S. Katie Schofield & Matty Graham, Exponential Performance Podcast/YouTube, (18 July 2017). Katie Schofield went from athletics to a world class track cyclist. As part of this podcast she discusses: Relative Energy Deficiency in Sport, her experiences and research (starts: 28.30).
  • Relative Energy Deficiency in Sport (RED-S). Dr Margo Mountjoy, Aspetar/YouTube, (30 March 2015). Dr Margo Mountjoy talks about the pathophysiology and evolution of Relative Energy Deficiency in Sport (RED-S). She discusses the implications of RED-S in terms of health and performance and how male athletes are affected. In addition to this, Dr Mountjoy proposes the RED-S clinical assessment tools for screening and return to play.
  • Female Athlete Triad and Its Components: Toward Improved Screening and Management, Mayo Proceedings/YouTube, (3 September 2013). Dr. Asma Javed, a Clinical Fellow in Pediatric Endocrinology at Mayo Clinic in Rochester, MN, provides clarity to the condition known as "Female Athlete Triad" as a range of conditions surrounding disordered eating, amenorrhea, and bone loss in women athletes, which is best treated with nutrition repletion. 

Clearinghouse Videos 

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