Relative Energy Deficiency in Sport: why it should be on all athletes’ radar

Relative Energy Deficiency in Sport (RED-S) is not exclusive, impacting athletes at any level, gender and age. Athletes who have spoken out about their experiences with RED-S include Pippa Woolven (GB distance runner, and founder of Project RED-S), Jake Riley (US distance runner), Susie Dear (rower), Evie Richards (British cyclist) and Phoebe Gill, who competed in the 800m Olympics earlier this month.

A syndrome of impaired physiological functioning including metabolic rate, hormonal and reproductive systems and cardiovascular health, RED-S is an imbalance that can lead to detrimental effects without prompt recognition. Coined by the International Olympic Committee in 2014, at its core it occurs when there is insufficient energy intake for expenditure, leading to low energy availability (LEA). High intensity or endurance training increases the risk, as does competing in weight class events, including lightweight rowing.

After prolonged periods of LEA, the body prioritises essential functions, leading to a wide range of effects, the signs of which can be well-disguised. Key features to be aware of are mood disturbances, anxiety, depression, frequent infections, disrupted sleep patterns, increasing injuries, along with irregular or absent periods in females, and in males the effects of reduced testosterone. These not only impact an individual’s well-being and training in the short term but have lasting consequences.

The Female Athlete Triad of low energy, menstrual disfunction and weakened bones, recognised prior to RED-S, now comes under its umbrella of signs. LEA from excess energy expenditure and/or disordered eating, being underweight, and stress are common precipitators for periods to become disordered or absent (Functional Hypothalamic Amenorrhea, FHA) because there is a lack of stimulation to the reproductive system. FHA can be masked by contraceptives, such as the withdrawal bleeds between packets of ‘the pill’ which do not represent a natural period. Although this may not present as problamatic – perhaps it might be convenient or even normalised as an athlete – periods are so much more than a monthly bleed. The hormones involved in the menstrual cycle have roles extending far beyond reproduction, affecting heart function, bone health and psychological wellbeing. The effects of these two entwined conditions amplify the impacts of each.

Both oestrogen and testosterone have key roles in bone turnover for male and female athletes – the decreased levels in LEA and/or FHA contribute to declining bone density, osteopenia and ultimately osteoporosis. This creates a serious predisposition to injury, particularly stress fractures. One study found a 4.5x increase in injury risk compared to equivalent athletes with normal-range oestrogen and testosterone. As shown by the stories of Bobby Clay, Jake Smith, Becky Briggs and Jess Piasecki – who have all suffered significant injuries as a result – it is too often not recognised until breaking point. Additionally, a lower-than-normal bone density leading up to peak bone mass around age 30 impairs the reserve for the natural decline that starts to occur shortly after, creating a concerning osteoporosis risk for later in life.

However pesky, each period is an important marker of health for female athletes. As a spectrum of sub-optimal health, precipitated by intentional or accidental energy mismatches, it is important to recognise signals of RED-S – and the sooner the better. From meeting individual nutritional needs to appreciating indicators of healthy functioning beyond performance, athletes should feel empowered about their health, aided by the support and awareness of coaches, teammates and the wider network around them.

(Main) Sources

1. Project RED-S
2. Correction: 2023 International Olympic Committee’s (IOC) consensus statement on Relative Energy Deficiency in Sport (REDs)
3. Hypothalamic Amenorrhea and the Long-Term Health Consequences (2017)
4. Reasons for and Consequences of Low Energy Availability in Female and Male Athletes: Social Environment, Adaptations, and Prevention (2020)
5. Relative Energy Deficiency in Sport in Male Athletes: A Commentary on Its Presentation Among Selected Groups of Male Athletes in International Journal of Sport Nutrition and Exercise (2019)

Athlete’s stories

https://www.runnersworld.com/uk/news/a29987241/jess-piasecki

https://olympics.com/en/news/diagnosed-with-osteoporosis-at-18-years-old-bobby-clay-s-warning-to-other-athlet

https://red-s.com/articles/student-athlete-advice

https://red-s.com/articles/founder-pippas-red-s-story

https://www.runnersworld.com/nutrition-weight-loss/a40303925/red-s-in-male-runners

https://www.laps.careers/when-power-to-weight-becomes-less-than-powerful

https://www.instagram.com/p/ClMZdnzLGTl/

https://www.redbull.com/gb-en/evie-richards-interview-red-s

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Hannah Joels

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