Relative Energy Deficiency in Sport (RED-S)

Relative Energy Deficiency in Sport (RED-S) is a condition that affects athletes and is characterized by a combination of physical and psychological symptoms caused by a reduction in energy available for essential biological processes. The condition results from an imbalance between energy intake and expenditure, leading to chronic low energy availability. This can occur from restriction of calories or an intense training regimen. Either way, it's a mismatch between what the body requires for optimal

functioning and what fuel it is being given. This has a profound impact on health, performance, and well-being.

The onset of RED-S has consequences throughout the body including the endocrine, musculoskeletal, cardiovascular, reproductive, psychiatric, and immune systems. This may manifest as decreased muscle mass and strength, stunted growth, decreased bone density, menstrual dysfunction, erectile dysfunction, fatigue, insomnia, decreased immunity, and decreased concentration and motivation.

One serious consequence is decreased bone density as it can be permanent. Low bone density accelerates osteoporosis (thin or weak bones) increases the risk of stress fractures and pathologic fractures. Irritability, insomnia and fatigue may be mistaken for anxiety or depression and treated with medications or psychotherapy when a diagnosis of RED-S would be more appropriate and require a different intervention. Additionally, RED-S can interfere with the hormonal regulation of the menstrual cycle in females increasing the risk of infertility.

Recognition of RED-S can be difficult in anyone as it can mimic many other conditions. Children and teenagers are especially susceptible to the effects as they require significant caloric intake to support normal growth and development and may be less mindful about how they fuel themselves for their sport. complicating matters is that in some sports, such as long distance running or cycling, the person may initially see faster times with increased training despite not having adequate food intake. In menstruating people, loss of periods (amenorrhea) always warrants investigation by a medical professional and should never be considered a "normal" part of a sport. In males, there is no specific sign like amenorrhea to watch for but frequent illness, anxiety or moodiness may be reason to investigate.

The treatment of RED-S optimally includes a multi-disciplinary approach that addresses both the physical and psychological aspects of the condition. This may include an increase in caloric intake to restore energy balance, as well as a reduction in training volume and intensity. Psychological support is often warranted to address the mental health impact. In addition, athletes should receive medical evaluation to screen for eating disorders and other mimicking conditions and to monitor for safe return to sports.

The best way to prevent RED-S is to maintain a balanced diet that provides adequate caloric and nutrient intake to support the demands of training and competition. Coaches and trainers should be aware of the symptoms of RED-S and should educate athletes about the importance of energy balance for health and performance.

In conclusion, RED-S is a condition that affects athletes and is characterized by a combination of negative physical and psychological symptoms caused by a reduction in energy available for essential biological processes. The condition results from an imbalance between energy intake and energy expenditure, and can have serious consequences for health, performance, and well-being. To prevent RED-S, it is important to maintain a balanced diet and monitor energy intake and expenditure, while also being aware of the symptoms of the condition. With the right treatment and support, athletes can overcome RED-S and return to optimal health and performance.

References:

Dipla K, Kraemer RR, Constantini NW, Hackney AC. Relative energy deficiency in sports (RED-S): elucidation of endocrine changes affecting the health of males and females. Hormones (Athens). 2021 Mar;20(1):35-47. doi: 10.1007/s42000-020-00214-w. Epub 2020 Jun 17. PMID: 32557402.

Kuikman MA, Coates AM, Burr JF. Markers of Low Energy Availability in Overreached Athletes: A Systematic Review and Meta-analysis. Sports Med. 2022 Dec;52(12):2925-2941. doi: 10.1007/s40279-022-01723-x. Epub 2022 Jul 11. PMID: 35819582.