Relative energy deficiency in sport

In order to perform at the top level in endurance sports, it is crucial that the athletes have sufficient energy availability. Relative Energy Deficiency in Sport (RED-S) and eating disorders are common problems in endurance sports and can have serious consequences for both health and performance.

Relative energy deficiency (RED-S)

Relative energy deficiency occurs when energy intake does not correspond to the amount of energy consumed, leading to an imbalance where the body does not receive enough energy to maintain basic physiological functions. This can lead to hormonal changes, menstrual disorders, reduced skeletal strength, increased risk of injury and reduced performance (Melin, A., et al., 2015).

Health consequences

• Hormonal changes: Relative lack of energy can cause reduced release of sex hormones, which can lead to menstrual disturbances in women and low testosterone levels in men. Menstrual disorders can in turn lead to reduced bone density and increased risk of osteoporosis (Stenqvist, TB, et al., 2023). In women, this can also mean that the menstrual cycle stops, which should not be seen as a normal sign of hard training but rather as a sign of severe energy deficiency (Melin, A., et al., 2015).

• Skeletal strength: Low energy availability can inhibit the development of the skeleton and increase the risk of osteoporosis. This is of particular concern to young athletes who are still developing their skeleton. One study found that many young male athletes had poor bone health already at baseline, meaning they did not reach the expected increase in bone density during puberty (Stenqvist, TB, et al., 2023).

• Metabolic problems: Lack of energy can lead to low resting metabolism, low blood sugar and blood pressure, and elevated cholesterol. These metabolic problems can impair the body's ability to recover from exercise and increase the risk of chronic diseases (Melin, A., et al., 2015).

Psychological and performance consequences

• Mental health problems: Increased risk of eating disorders, depression and other mental health problems are common among athletes who suffer from a relative lack of energy. The stress of maintaining a certain weight or body composition can lead to unhealthy eating habits and a negative self-image. This can create a vicious circle where the mental stress worsens the physical symptoms and vice versa (Stenqvist, TB, et al., 2023).

• Impaired performance: Low energy availability negatively affects endurance, muscle strength and judgment, impairing the athlete's performance. Athletes with a relative lack of energy have more difficulty maintaining the intensity and duration of their training, leading to poorer results in competitions (Mountjoy, M., et al., 2014).

Prevalence of RED-S and eating disorders

Studies show that relative lack of energy and eating disorders are not only a problem among female athletes, but also among male athletes. In endurance sports, the incidence of these problems is particularly high. One study found that over 60 percent of elite female athletes had a relative lack of energy, many without having a diagnosed eating disorder (Melin, A., et al., 2015).

Recommendations for handling RED-S

1. Education: Implement educational programs for coaches and athletes on the importance of adequate energy intake and early detection of RED-S. It is important to raise awareness of the risks of energy deficiency and encourage a healthy and balanced diet (Mountjoy, M., et al., 2014).

2. Screening: Regular health checks to identify early signs of energy deficiency and menstrual disorders. Screening should include both physical and psychological assessments to get an overall picture of the athlete's health (Stenqvist, TB, et al., 2023).

3. Individualized advice: Offer nutritional advice and support from dietitians to ensure athletes are getting enough energy to meet their physiological needs. Diet plans should be tailored to each athlete's specific training load and energy needs (Melin, A., et al., 2015).

4. Psychological support: Provide access to psychologists and other experts to deal with the psychological aspects of eating disorders and energy deficiency. Psychological support can help athletes develop a healthier relationship with food and exercise as well as manage stress and performance anxiety (Mountjoy, M., et al., 2014).

Summary

Relative lack of energy and eating disorders are significant problems in cross-country skiing and other endurance sports. To optimize the health and performance of athletes, early identification and treatment of these conditions is critical. Through education, screening and support, we can improve athletes' well-being and performance.

References

• Melin, A., Tornberg, Å., Skouby, S., & Sundgot-Borgen, J. (2015). Lack of energy is a major health problem among the female elite. Swedish Sports Research, 1, 14-17.
• Stenqvist, TB, Melin, AK, & Torstveit, MK (2023). Relative Energy Deficiency in Sport (REDs) Indicators in Male Adolescent Endurance Athletes: A 3-Year Longitudinal Study. Nutrients, 15(12), 5086.
• Mountjoy, M., Sundgot-Borgen, J., Burke, L., Carter, S., Constantini, N., Lebrun, C., ... & Ljungqvist, A. (2014). The IOC consensus statement: beyond the Female Athlete Triad—Relative Energy Deficiency in Sport (RED-S). British Journal of Sports Medicine, 48(7), 491-497.