Low Energy Availability in Exercising Women: Historical Perspectives and Future Directions

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. While early cross-sectional studies focused primarily on menstruation, research has progressed to now encompass hormonal changes, bone health and lipid profiles. The seminal work of Loucks and colleagues distinguished that these health concerns were due to low energy availability (LEA) rather than exercise alone. LEA occurs when the body has insufficient energy available to meet the needs of training and normal physiological functioning. While there appears to be agreement that LEA is the underlying cause of this syndrome, controversy regarding terminology has emerged. Originally coined the female athlete triad (Triad), some researchers are now advocating the use of the term relative energy deficiency in sport (RED-S). This group argues that the term Triad excludes male athletes who also have the potential to experience LEA and its associated negative impact on health and performance. At present, implications of LEA among male athletes are poorly understood and should form the basis of future research. Other directions for future research include determination of the prevalence and long-term risks of LEA in junior and developmental athletes, and the development of standardised tools to diagnose LEA. These tools are required to aid comparisons between studies and to develop treatment strategies to attenuate the long-term health consequences of LEA. Continued advances in knowledge on LEA and its associated health consequences will aid development of more effective prevention, early detection and treatment strategies.