“…More specifically, the project engaged quantitative and qualitative research data from: (i) a survey gathering initial demographic, training, and nutritional information; (ii) physiological measures, including resting metabolic rate (RMR) to establish current energy availability status, a dual-energy X-ray absorptiometry (DEXA) scan to assess body composition (particularly per cent body fat, fat mass, lean body mass and bone health), baseline blood work to measure key hormonal changes related to RED-S (estradiol, progesterone, testosterone, DHEA, iron status, cortisol, C-reactive protein, hepcidin, and thyroid function); and (iii) semi-structured interviews. The same methodology was repeated across two different sports (endurance multi-sport, rugby), with the first phase including 12 elite, non-professional endurance female athletes (competing in triathlon and/or Ironman events), (Thorpe and Clark, 2020), and the second phase including 18 members of a national rugby sevens team (Thorpe et al, 2019).…”