Background Athlete health, training availability and performance can be impeded due to Relative Energy Deficiency in Sport (RED-S). Development of RED-S is underpinned by low energy availability (LEA), however its natural history is yet to be defined.
Objective To quantify the prevalence of issues previously described in association with RED-S in a mixed-sport cohort of female athletes, to inform the definition of its natural history.
Design This cross-sectional, observational study in athletes from eight sports utilised validated screening questionnaires and clinical investigations.
Setting Athletes were competing and/or training at a state, national or international level at the time of recruitment. Questionnaire data were collected electronically, whilst clinical investigations were undertaken at the Australian Institute of Sport.
Participants Females ≥15 years old from the National Sporting Organisations approached by the researchers were eligible (n=112).
Assessment of Risk Factors Psychology, nutrition and sleep screening questionnaires were administered. Fasted blood tests, indirect calorimetry, dual-energy x-ray absorptiometry scans, and diagnostic psychiatric clinical interviews were undertaken.
Main Outcome Measurements Menstrual function, bone mineral density, thyroid function, resting metabolic rate, serum ferritin, mental health, lipid profile, gastrointestinal symptoms and recent illness and/or injury resulting in sports incapacity were assessed as indicators of the health consequences associated with RED-S.
Results Almost all (87%) participants demonstrated at least one indicator of RED-S consequences, with 81% exhibiting between one and three indicators. Participants most commonly displayed impairments of the immunological (24%), cardiovascular (28%), haematological (29%) and gastrointestinal (46%) systems. Risk of LEA was identified in 11–55% of participants, and one third of the assessed cohort had a diagnosed psychiatric condition.
Conclusions RED-S consequences were prevalent.
These results have informed secondary prevention strategies whereby early detection of symptoms leads to early intervention prior to multi-system involvement. Further work is warranted to determine the interactions between these impairments, LEA and subsequent RED-S, to inform treatment and prevention.