Relative Energy Deficiency in Sport, or REDS for short, is defined as follows by the International Olympic Committee:

a syndrome of impaired physiological and/ or psychological functioning experienced by female and male athletes caused by exposure to problematic (prolonged and/ or severe) low energy availability. The detrimental outcomes include but are not limited to decreases in energy metabolism, reproductive function, musculoskeletal health, immunity, glycogen synthesis, cardiovascular and haematological health which can all individually and synergistically lead to impaired well- being, increased injury risk, and decreased sports performance.

REDS is an unfortunately commonplace thing in endurance sport. Fortunately, there is more and more information available about it. Below are some handouts to help you to recognise some of the causes and symptoms associated with REDS, including underfueling, bone health, and amenorrhea.