Methodology for studying Relative Energy Deficiency in Sport (REDs): a narrative review by a subgroup of the International Olympic Committee (IOC) consensus on REDs.

In the past decade, the study of relationships among nutrition, exercise and the effects on health and athletic performance, has substantially increased. The 2014 introduction of Relative Energy Deficiency in Sport (REDs) prompted sports scientists and clinicians to investigate these relationships in more populations and with more outcomes than had been previously pursued in mostly white, adolescent or young adult, female athletes. Much of the existing physiology and concepts, however, are either based on or extrapolated from limited studies, and the comparison of studies is hindered by the lack of standardised protocols. In this review, we have evaluated and outlined current best practice methodologies to study REDs in an attempt to guide future research.This includes an agreement on the definition of key terms, a summary of study designs with appropriate applications, descriptions of best practices for blood collection and assessment and a description of methods used to assess specific REDs sequelae, stratified as either Preferred, Used and Recommended or Potential Researchers can use the compiled information herein when planning studies to more consistently select the proper tools to investigate their domain of interest. Thus, the goal of this review is to standardise REDs research methods to strengthen future studies and improve REDs prevention, diagnosis and care.

Prevalence of impaired physiological function consistent with Relative Energy Deficiency in Sport (RED-S): an Australian elite and pre-elite cohort.

OBJECTIVES: Athlete health, training continuity and performance can be impeded as a result of Relative Energy Deficiency in Sport (RED-S). Here we report the point prevalence of symptoms described by the RED-S model in a mixed-sport cohort of Australian female athletes. METHODS: Elite and pre-elite female athletes (n=112) from eight sports completed validated questionnaires and underwent clinical assessment to assess the point prevalence of RED-S symptoms. Questionnaires included the Depression, Anxiety and Stress Questionnaire (DASS-21), Generalized Anxiety Disorder (GAD-7), Center for Epidemiological Studies Depression Scale (CES-D), SCOFF questionnaire for disordered eating, Low Energy Availability in Females Questionnaire (LEAF-Q), and a custom questionnaire on injury and illness. Clinical assessment comprised resting metabolic rate (RMR) assessment, dual-energy X-ray absorptiometry-derived body composition and bone mineral density, venous and capillary blood samples, and the Mini International Neuropsychiatric Interview (MINI 7.0.2). Descriptive prevalence statistics are presented. RESULTS: Almost all (80%) participants (age 19 (range 15-32) years; mass 69.5±10.3 kg; body fat 23.1%±5.0%) demonstrated at least one symptom consistent with RED-S, with 37% exhibiting between two and three symptoms. One participant demonstrated five symptoms. Impaired function of the immunological (28%, n=27), haematological (31%, n=33) and gastrointestinal (47%, n=51) systems were most prevalent. A moderate to high (11%-55%) prevalence of risk of low energy availability was identified via RMR and LEAF-Q, and identified mental illnesses were prevalent in one-third of the assessed cohort. CONCLUSION: Symptoms described by the RED-S model were prevalent in this cohort, supporting the need for improved awareness, monitoring and management of these symptoms in this population.