It is well established that regular exercise and physical activity promote numerous health benefits for girls and women (1, 2). However, under some conditions and in some girls and women, participation in sports and exercise can be associated with negative health outcomes. There are currently two schools of thought and corresponding conceptual models regarding the potential for negative health outcomes of participating in sports and exercise: the Female Athlete Triad (Triad;(2–4)) and Relative Energy Deficiency in Sport (RED-S;(5–7)). The Triad is referred to in position stands from 1997 (8) and 2007 (2), and a recent consensus statement in 2014 (3, 4), and RED-S is the topic of a consensus statement from 2014 (5) and a recent update (6). Both the Triad and RED-S statements call attention to the importance of adequate energy intake to prevent negative health outcomes associated with the participation in sport and exercise. They both include point system algorithms for risk stratification and decision-making on clearance and return to play. However, the Triad and RED-S models differ in several ways, including the target audience and scope of outcomes. The Triad refers to girls and women and is focused on low energy availability and associated clinically relevant outcomes, for example, disordered eating, menstrual dysfunction, and bone loss (2–4). RED-S covers a broader array of both physiological and performance outcomes in both women and men and calls for more research on the impact of race, ethnicity, and disability (5, 6). The two statements also differ in the way supporting evidence and scientific rigor are interpreted and incorporated into the models representing each syndrome. The authors of the more recent RED-S consensus statement consider the RED-S model to be more comprehensive than the Triad model and have, therefore, called for the “replacement” of the Triad with RED-S (5). An alternative view is that replacing the Triad with RED-S will a) dilute the emphasis on girls and women when it is they who experience the most severe medical consequences and, thus, need the most attention, b) downplay the clinical relevance of eating disorders, menstrual disturbances, and low bone mass as the primary medical