Why Low Energy Availability Doesn’t Have a “Look”
- Melissa Hardy PDt, CDE, CSSD, IOC Sport Nutrition Diploma.
- Jun 23
- 6 min read
Health isn’t visible. Food isn’t optional. Low energy availability doesn’t have a look.
Written by Melissa Hardy, RD, CDE, CSSD, IOC Diploma in Sport Nutrition, with contributions from Dietetic Intern Sonia Rondon.
The reality is: you cannot assess health or fuelling status based on appearance, period.
Low Energy Availability (LEA) happens when the energy (calories) consumed doesn’t cover both the demands of training and the basic energy required to keep the body running smoothly. After exercise is accounted for, there simply isn't enough left to fuel key systems like hormone production, digestion, bone health, or recovery, putting the athlete in a physiological state of LEA. Don’t get me wrong, the body will still “run”, but it will be FAR from optimal function!
Your body runs on energy. Every system- heart, brain, reproductive, immune, digestive, requires calories to function. Calories are the currency of life! When fuel is low, the body enters a conservation mode: it prioritizes essential functions like brain and heart activity. Basically, it keeps the lights on where it has to, but powers down where it can, such as, hormones, bones, digestion, mood, energy, immunity. This affects athletes of all body types, in all sports, and of every gender.
In fact, emerging research shows that athletes in larger, stronger, or higher-weight bodies may be at equal or even greater risk of LEA. This is often overlooked because they don’t necessarily “look” under fuelled - more on that later!
LEA Exists on a Spectrum
LEA isn’t as simple as black or white. It exists on a continuum:
There’s Adaptable LEA: Short-term, mild deficits that may reverse with appropriate fuelling. These are like a weekend of binge drinking- yes, there are negative effects, but the body often bounces back with appropriate rest and recovery.
And Problematic LEA: Chronic or severe deficits causing long-term impairment to multiple systems. This is more like long-term alcohol abuse. The effects aren’t just short-term; they can become deeply embedded in multiple systems and take months or years to reverse - if at all.
The dose and duration of energy deficiency matter most. The longer an athlete remains in a state of problematic LEA, the harder recovery becomes- both physically and psychologically.
Prolonged LEA can lead to Relative Energy Deficiency in Sport (REDs), a clinical syndrome that affects both physical and mental function. REDs doesn’t just target one area of health- it can impair hormones, bone health, immune defence, mood, digestion, and cardiovascular performance. REDs is a serious medical condition that is often invisible. It can affect athletes across all disciplines, body types, and gender identities. It’s easy to miss, as many athletes don’t realize they’re under fuelling, and denial is common. But the body always notices. What may start as fatigue, decreased sex drive, low moods, frequent colds, or disrupted periods can evolve into long-term consequences if not addressed.
Why LEA Occurs More Frequently Than We Realize
Many athletes don’t intentionally under fuel. LEA often happens due to simple mismatches:
Long or double training sessions
Travel and competition schedules
Appetite suppression after intense workouts
Busy lifestyles with limited time or resources to prepare adequate meals
It’s shockingly easy for even highly motivated athletes to fall into an energy deficit without realizing it. Below are subtypes of LEA and examples.
Recent research from Gowers et al. (2025) highlights something critical:
77% of female endurance athletes at risk of LEA had higher body weight and body fat compared to their peers who were not at risk.
This directly challenges the harmful assumption that only “thin” athletes are at risk.
Similarly, among male endurance athletes, 31% had low bone mineral density (BMD), often undetected clinically. These athletes may appear strong and muscular but still suffer from silent consequences of LEA.
Athletes in larger or stronger bodies are at risk of eating disorders too, and it’s important to note that eating disorders can affect athletes of all body types. However, athletes in larger or stronger bodies, and at higher weights, may face unique challenges that put them at risk for disordered eating or eating disorders. Here’s why:
In my experience working with athletes, those in larger or stronger bodies often experience the most significant energy deficits, yet they’re frequently overlooked.
These athletes may be “sick enough” to meet criteria for LEA and be experiencing serious health and performance consequences, but they don’t always meet the narrow diagnostic criteria outlined in the DSM-5 for eating disorders. Their physical appearance, or anthropometric data, doesn’t always raise red flags, allowing them to fly under the radar during routine medical visits.
Their concerns may be dismissed or invalidated, both by themselves and by providers. Athletes might rationalize restrictive behaviours by saying, “I’ve only cut carbs” or assume they’re healthy because, “my BMI is high.” Unfortunately, physicians - often the first point of contact, may not recognize the problem if the athlete doesn’t “look underweight.” This contributes to delayed care and worsening symptoms.
Weight bias in healthcare is widespread, and athletes are not exempt. Clinicians who aren’t trained in eating disorders, LEA, or REDs often miss the warning signs. That’s why it’s essential that our assessments include intentional questions about an athlete’s relationship with food, their body, and their sport - not just weight or BMI.
What Does LEA Actually Look Like?
You won’t see LEA on the scale. Instead, you see it in:
How The Body Hides LEA: Metabolic Adaptations
LEA triggers adaptive changes that can mask outward signs.
Lower resting metabolic rate (the body burns fewer calories at rest)
Hormonal changes: thyroid suppression, reproductive hormone downregulation
Muscle loss may be undetected on a regular scale due to fluid shifts or fat redistribution
This is why many athletes remain weight stable, or even gain weight, while in prolonged LEA.
"If anyone is 100% confident in the simplistic view of 'calories in vs calories out,' it highlights what they don’t know." - a sentiment echoed across recent LEA research.
LEA doesn't just affect bones and hormones; it takes a toll on mental health, too.
Depression, anxiety, obsessive thoughts about food, exercise or body image.
Emotional burnout, low motivation, and identity issues tied to sport.
Increased injury risk leads to frustration and fear of returning to play.
In Gowers et al. (2025), athletes at risk for LEA also scored higher on burnout and psychological strain assessments.
The relationship works both ways: mental stress can trigger LEA, and LEA can worsen mental health.
What Can You Do?
Stop assuming health based on appearance. Start asking better questions.
Whether you're a clinician, coach, parent, or athlete, it’s time to look beyond weight and body size and consider:
· Are they eating enough to support training and recovery?
· Are they experiencing recurring injuries, persistent fatigue, or mood changes?
· Are menstrual cycles regular? Is growth or development on track?
· Are they avoiding or restricting certain foods or food groups?
· Are they preoccupied with body composition or performance?
· Are they struggling emotionally during rest periods, injury, or time off?
Early intervention leads to better outcomes. Prevention starts with education, awareness, and creating safe spaces where athletes feel comfortable voicing concerns. The goal? A future where sport organizations have clear policies for REDs prevention, detection, and treatment- prioritizing athlete health above all else.
The Bottom Line:
If we continue to screen based on appearance, we will continue to miss and harm athletes. You won’t see LEA by looking. But you will notice the patterns. The warning signs. The missed cues. Know what to look for. Speak up early. Let’s end the myth that LEA has a “look.” Because believing that? That’s how we miss it!
Burke, L. M., Ackerman, K. E., Heikura, I. A., Hackney, A. C., & Stellingwerff, T. (2023). Developing a physiological model for Relative Energy Deficiency in Sport (REDs): An IOC subgroup study. British Journal of Sports Medicine, 57(17), 1098–1110. https://doi.org/10.1136/BJSPORTS-2023-107335
Burke, L. (2024). REDs: Where to from here [Webinar]. The Sports Oracle.
Gowers, C. R., McManus, C. J., Chung, H. C., Jones, B., Tallent, J., & Waterworth, S. P. (2025). Assessing the risk of low energy availability, bone mineral density and psychological strain in endurance athletes. Journal of Sports Sciences, Advance online publication. https://doi.org/10.1080/15502783.2025.2496448
Melin A, Tornberg ÅB, Skouby S, Møller SS, Sundgot-Borgen J, Faber J, Sidelmann JJ, Aziz M, Sjödin A. Energy availability and the female athlete triad in elite endurance athletes. Scand J Med Sci Sports. 2015 Oct;25(5):610-22. doi: 10.1111/sms.12261. Epub 2014 May 30. PMID: 24888644
