We hear a lot about the importance of staying active for fitness and health. Some athletes take physical activity to an even higher level with more extended and intense workouts to get a competitive edge. To keep up with these demands, the body requires more fuel and more nutrients. Athletes who do not provide for these additional needs, may notice reduced performance and other negative effects. 

Several years ago, members of the International Olympic Committee released a consensus statement defining a term that describes this syndrome of low energy availability – relative energy deficiency in sports (RED-S). They described it as “impaired physiological function including metabolic rate, menstrual function, bone health, immunity, protein synthesis and cardiovascular health caused by relative energy deficiency." 

Other noted effects can be gastrointestinal problems, increased risk of injury, decreased muscle strength, and impaired judgment, among others. Mood fluctuations, dizziness, and increasing fatigue may be other noted symptoms. 

Although compared to the average person serious athletes may appear to consume large amounts of food, their fuel demands may be even higher. This calorie and nutrient deficit starts a downward spiral that can create a number of performance and health concerns. 

The focus on this syndrome evolved from a term coined several decades ago — the female athlete triad. The triad was a recognized association seen in athletic women of having an eating disorder, loss of menstrual cycling, and osteoporosis. The result was poor performance, as well as possible short- and long-term health consequences. The committee wanted to expand the definition based on updated research and so modified the description somewhat, which also includes concerns related to male athletes.

Similar to the triad, the RED-S definition includes three related conditions — low energy availability, with or without disordered eating, menstrual dysfunction and low bone mineral density. Be aware that all these symptoms and health concerns do not have to occur at the clinical level, may not necessarily occur at the same time or at the same level of intensity.

In RED-S, energy availability is defined as the energy provided by dietary fuel minus the demand from physical activity. What remains is the fuel left to support all other body functions. When sufficient fuel is not provided by the diet, low energy availability is the result. Note that a low body weight is not always the outcome of RED-S. Even normal weight athletes can be experiencing it.

Active individuals who may be at greater risk for RED-S might be those who are going through a period of growth, those restricting categories of food (vegans, vegetarians, those eliminating one or more food groups, etc.), those involved in sports emphasizing thinness or weight regulation, people who are overtraining, athletes whose coaches encourage behaviors related to unhealthy habits, those doing sport-specific training from a young age, and people at risk for certain nutrient deficiencies.

In evaluating an athlete for RED-S, the recommendations might include an annual exam, questions about menstrual history in females, history of dieting behaviors and patterns, weight history, blood work assessing possible nutrient deficiencies, feelings about body size and image, history of stress fractures or other low trauma fractures, history of excessive injuries/illnesses, changes in emotional status (mood shifts, depression, etc.), frequent dizziness, cold sensitivity, and intestinal issues.

Until dietary energy availability and nutrients are sufficient, the athlete cannot reach their genetic athletic potential. They may also be experiencing both short- and long-term health problems. Plus, they may not be enjoying their activity as much due to extreme fatigue and lack of muscle recovery.

With regard to female athletes, an extended length of time without a menstrual cycle can cause bone loss that may not be recoverable. Extensive loss of bone density might mean giving up impact activities long-term due to the risk of fracture.

In team sports, the coach, parent, health care provider, or other decision-maker looking out for the best interest of the athlete, may recommend abstaining from physical activity until the concerns are resolved. This is to ensure the safety of the athlete and to reduce the harmful consequences of ongoing RED-S.

In creating a plan moving forward, the athlete can find support in a team of professionals – a health care provider, a registered dietitian, and a psychotherapist (ideally those who work with athletes). If the athlete is working with a trainer and/or coach all these professionals can assist the athlete in creating a timeline/plan for establishing appropriate athletic goals.

The plan should include timing, types, and amounts of food that will provide sufficient calories, carbs, protein, and dietary fat. It should also take into account nutrient needs and sources based on the intended exercise. Iron, calcium, vitamin D, and the antioxidants found in fruits and vegetables are some examples of important nutrients for athletes.

So if you are an athlete experiencing some of the symptoms of RED-S, consider what steps you can take so that you can improve your energy level, maximize your performance, counter potential health problems, and continue to enjoy the physical activity you love for a long time.

Pam Stuppy, MS, RD, CSSD, LD, is a registered, licensed dietitian with nutrition counseling offices in York, Maine, and Portsmouth. She is also the nutritionist for Phillips Exeter Academy, presents workshops nationally, and is board certified as a specialist in sports dietetics. See www.pamstuppynutrition.com for nutrition information, healthy cooking tips and recipe ideas.