The Female Athlete Triad was given its formal name during the consensus conference by the American College of Sports Medicine (ACSM). In 2014, the International Olympic Committee (IOC) Consensus Statement defined the female athlete triad as a combination of disordered eating and irregular menstrual cycles which lead to a decrease in oestrogen and other hormones, further resulting in low bone mineral density. However, some researchers show that this is not a triad of three combinations but rather a syndrome which is much broader than originally thought. They believe it is caused by an energy deficiency relative to the balance between energy intake and energy expenditure required for health, daily living, growth and physical activity. The IOC introduced a broader more comprehensive term known as Relative Energy Deficiency in Sport or RED-S.
The syndrome RED-S refers to ‘the impaired physiological function, including metabolic rate, menstrual function, bone health, immunity, protein synthesis and cardiovascular health’. This is caused by the relative energy deficiency or low Energy Availability (EA) in male and female athletes of all ages and levels. RED-S can have a huge impact on an athletes quality of life and performance.
The underlying problem of RED-S is a low energy availability (EA). This is where the energy intake (foods/fluids we consume) is lower than the energy we expend out through physical activity/exercise. A low EA may hinder an athletes performance in the short and long term. Not consuming enough energy can result in muscle loss, reduced performance, slow recovery, disruption of hormonal function for females and increased risk of fatigue, injury and illness.
RED-S is very common in athletes participating in sports where being lean and having a low body weight is a priority, for example, in sports like running, gymnastics, ballet, figure skating, swimming, weight lifting and bodybuilding. To achieve this goal of being lean and having a low body weight, many athletes will restrict their eating, while still participating in their intense and excessive training sessions. This can cause an obsessive preoccupation with body weight and calorie intake, which can lead to disordered eating. The prevalence of disordered eating is 20% higher in athletes compared to non athletes. One study of elite female athletes from eight different sports showed that almost all (80%) of participants aged 15-32years demonstrated at least one symptom with RED-S. There was also a moderate to high prevalence of risk for low EA and mental illness were prevalent in one third of athletes.
Although most of the research in this field has mainly been female athletes, there is a lot of evidence where male athletes are also affected by RED-S. Male athletes in sports like cycling and weight class sports have been shown to have disordered eating behaviours or an eating disorder. Some male athletes with RED-S appear to have a lower immune function, impaired bone health, low sex hormones and impaired reproductive function. One study of 108 male endurance athletes (runners, cyclists and triathletes) indicated a moderate to high prevalence of low EA with nearly 80% of participants at risk of experiencing low EA. In this cohort, cyclists were at greater risk of low EA.
For prevention and early intervention, it is crucial to educate athletes, coaches, parents, and trainers. The main aim of treatment for RED-S is to reverse the underlying problem of low EA. This would include increasing dietary intake and/or decreasing energy expenditure by reducing exercise intensity and duration. The treatment for menstrual dysfunction is to begin increasing body weight and ensuring an adequate amount of protein and carbohydrates are consumed. A diet high in calcium and vitamin D is recommended for athletes with bone disorders like osteopenia and osteoporosis. The use of the oral contraceptive pill for the treatment for RED-S is not recommended as it may have negative effects on bone health. There should also be a treatment plan where psychological and medical support are required for athletes who may have an eating disorder or disordered eating. A multidisciplinary treatment team should be put in place including a registered dietitian, physician, a mental health practitioner as well as the certified trainer, coach, parents and family members.
In summary, RED-S can have a huge impact on an athletes quality of life and performance. The underlying problem of low EA may hinder an athletes performance and result in muscle loss, reduced performance, slow recovery, menstrual dysfunction and increased risk of fatigue, injury and illness. It is common in both male and female athletes who participate in sports like cycling, running, gymnastics, ballet, figure skating, swimming, weight lifting and bodybuilding. A multidisciplinary team is necessary for the treatment of RED-S and should include the athlete, coaches, trainers, family members, dietitian, psychologist, etc. A treatment plan is needed for the athletes low EA, menstrual dysfunction, bone health and medical support for those who may have eating disorders or disordered eating.
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