Relative Energy Deficiency in Sport
A delay in starting the menstrual cycle (referred to as menarche) or periods becoming irregular/absent can be caused by energy deficiency specifically termed relative energy deficiency in sport (RED-S). This occurs when there is low energy availability, and the intake is not sufficient to cover the energy demands of exercise training and bodily processes. It can affect male and female athletes of all levels and ages.
A balance of dietary energy intake and energy expenditure is required for health and activities of daily living, growth and supporting activities. RED-S can affect menstrual function, metabolic rate, bone health, immunity, and cardiovascular health, among other things. It can also impact performance with female participants experiencing a decreased response to training, impaired coordination, and increased risk of injury.
Even when body weight is steady, low energy availability may be present due to high/increased training loads and endocrine or metabolic adaptations occurring to prevent weight loss. Initially performance (results) can appear to improve in the early stages, but this is a poor indicator of health, well-being and longer-term benefits. In females, a loss of or irregular periods are a sign of RED-S.
It is important to have an awareness of the negative impact of RED-S on health and performance. Factors such as specific body types (aesthetic) or weight-making sports can increase the risk and influencing factors. Sports with a focus on leanness (e.g., gymnastics, endurance and weight categories) can be a higher risk.
Always carefully consider recommendations in changes to weight and discuss these with a registered dietician/nutritionist before speaking to a participant.
For management of RED-S/amenorrhea, it is advised to seek medical advice and restore the optimal balance between training, nutrition, and recovery. This needs an integrated support network with medical guidance. Don’t avoid conversations or ignore menstrual dysfunctions.
What could you change to improve awareness of the importance of regular periods and support the female participants that you coach? What could you do to implement self-monitoring for cycle length and symptoms with your participants?