Why your gut issues, fatigue or injuries might not be what you think (and what to do about it)

Are you a runner dealing with ongoing fatigue, gut issues, poor recovery, or feeling like your performance just isn’t where it should be? You’ve probably already looked at your fueling, hydration, or training plan. But if things still aren’t improving, it may be time to look a little deeper. Because sometimes, the issue isn’t just what you’re doing. It’s what’s sitting underneath it.

Sometimes, the very thing that seems to be helping your performance in the short term… is what’s holding you back long term.

Disordered eating in endurance athletes (and why it’s often missed)

Disordered eating and eating disorders are more common in endurance athletes than most people realise. And importantly, they don’t always look obvious. It’s not always a diagnosed eating disorder. Instead, it exists on a spectrum, from optimised nutrition, through disordered eating, to clinical eating disorders. Which means many athletes sit somewhere in the middle, where things don’t feel quite right, but aren’t clearly identifiable either.

It often shows up as:

• Avoiding fuel during training due to fear of weight gain
• Rigid rules around food or “clean eating”
• Cutting out foods or food groups
• Feeling like you need to “earn” food through training
• Training loads that are difficult to switch off from
• Training through fatigue or injury
• Struggling to fuel during long runs
• Constant thoughts about food or body
• Difficulty concentrating or being present
• Avoiding social situations involving food

From the outside, this can look like discipline. But internally, it’s often consuming, and it places significant stress on the body.

How underfuelling affects performance

When your body doesn’t get enough energy, it affects every system involved in performance.

Common signs of underfuelling in runners include:

• Persistent fatigue
• Poor recovery
• Gut symptoms during exercise
• Recurrent injuries
• Reduced training consistency
• Plateaued or declining performance
• Sessions feeling harder than expected
• Loss of motivation or enjoyment
• Difficulty concentrating
• Cycles of restriction followed by overeating

This is where it can get confusing. In some cases, performance may improve temporarily with weight loss or increased dietary restriction. You might feel lighter. You might run faster, for a while. But this is usually short-lived. As energy availability drops, the body begins to prioritise survival over performance, and the signs of under-fuelling start to become more apparent. So while it can look like it’s working in the short term, it rarely holds up, especially in endurance sport. And importantly - you can be weight stable and still be under-fuelling.

If you’re unsure whether this applies to you, you might find this helpful:
👉 "How do I know if I'm underfueling my running?"

“I didn’t realise how much I was under fuelling before I started working with Erin…”

The link between low energy availability and REDs

Chronic under-fuelling leads to low energy availability (LEA). This can occur with or without disordered eating, but often the two overlap. Over time, this can progress to Relative Energy Deficiency in Sport (REDs), affecting:

• Hormones
• Bone health
• Gut function
• Immune system
• Recovery and adaptation

It can also increase the risk of illness, injury, and gastrointestinal issues.

How common is disordered eating in athletes?

Disordered eating in athletes is not rare. Over 1.1 million Australians live with an eating disorder. Around 19% of male and 45% of female athletes experience disordered eating or eating disorders. More recent research in ultra-endurance athletes shows that around 11% meet clinical thresholds for eating disorder risk, over 20% display disordered eating behaviours, and importantly, training volume is a key driver of risk.

This means many athletes experiencing fatigue, gut issues or injuries may be dealing with underlying under-fuelling, particularly as training loads increase.

Why it’s often missed

Many of these behaviours are normalised within endurance sport.

The AIS and NEDC highlight that warning signs are often masked because:

• Restrictive eating can look like discipline
• High training loads can hide excessive exercise
• Body composition focus is often encouraged
• Preoccupation with food can be seen as commitment

Common myths about eating disorders in athletes

Misconceptions often prevent athletes from recognising or addressing the issue.

“I’m not underweight, so I’m fine.”
Eating disorders can occur at any body size.

“This is just discipline.”
Disordered eating is not discipline - it can impair performance and health.

“Eating disorders only affect women.”
They affect males and females across all levels.

“I should be able to snap out of it.”
These are complex mental health conditions that require support.

Why this matters for performance (and health)

Low energy availability doesn’t just affect race day. It impacts your ability to adapt to training, recover properly, maintain bone strength, stay injury-free and perform consistently.

👉 Health must come before performance

This is a key part of the work I do

Many athletes come to me for gut issues or performance concerns. But often, part of the solution is addressing underlying fuelling patterns and relationship with food.

I am an ANZAED Credentialed Eating Disorder Clinician, which means I have completed additional recognised training and meet strict criteria to provide safe, evidence-based care for individuals experiencing eating disorders and disordered eating.

This sits alongside my qualifications as an Accredited Practising Dietitian and Accredited Sports Dietitian, and reflects experience working within multidisciplinary care - alongside GPs, psychologists and other health professionals.

The AIS and NEDC recommend a multidisciplinary approach, including a doctor, sports dietitian and psychologist, for best-practice care in this space. This is the model I work within when supporting athletes.

“Erin approaches her clients with compassion and understands the intertwined nature of mindset and eating habits.”

Practical steps to start improving your fuelling

If this resonates, you don’t need to change everything at once.

Start with a few simple steps:

1. Review your fuelling across the week
Are you eating enough consistently, not just on long run days? Mid-week sessions can still demand a significant energy requirement, and under-fuelling here often shows up later in the week.

2. Notice any food rules or rigidity
Do you catch yourself labelling foods as “good” or “bad”, or feeling like certain foods are off-limits? Aim for more flexibility - all foods can, and should, have a place in supporting both health and performance.

3. Shift your focus away from weight
Bring your attention back to energy, performance and overall wellbeing. You may notice this carries over into daily life too - better focus at work, more patience, and more capacity for the things that matter to you.

4. Reframe movement
Exercise should support your performance - not be used to compensate for food. Exploring different ways to move your body, like yoga or a watch-free run, can help you reconnect with movement as something to enjoy, rather than something you have to do to “earn” or deserve food.

5. Create a supportive environment
Pay attention to what’s influencing your thinking. Reducing exposure to negative body talk or diet culture messaging, and curating your social media to align with your goals, can make a meaningful difference.

6. Seek support early
You don’t have to figure this out on your own. Early support leads to better outcomes, and having the right team around you, alongside support from people you trust, can make the process much easier.

What happens when you address under-fuelling

When fuelling improves:

• Energy increases
• Recovery improves
• Gut symptoms often settle
• Training becomes more consistent
• Performance progresses

And just as importantly, your relationship with food can change.

“Your sessions really helped to improve my relationship with food. I now not only see food as a way to fuel my training, but as a part of living a full, fun and healthy life.”

If this sounds like you

If you’re dealing with fatigue, gut issues, or performance that isn’t improving despite your efforts, a poor relationship with food and your body may be part of the picture.

This is something I support athletes with every day, in a way that is practical, individualised, and evidence-based. Because often, the solution isn’t more discipline. It’s fuelling your body properly.

If this resonates, and you’d like clarity on what’s really going on for you, I’d be very happy to help. I offer a complimentary 30-minute Performance Strategy Call, where we take a considered look at your training, nutrition and overall picture, and map out a clear, individualised way forward.

Additional support options in Australia

Additional support services include:

• The Butterfly Foundation
• Beyond Blue
• Lifeline

If you are concerned you may be experiencing an eating disorder, you can speak with your GP about an Eating Disorder Treatment and Management Plan, which provides access to Medicare-supported care, including up to 20 dietetic sessions and 40 psychological sessions over 12 months. You can also visit Connect.ed to find ANZAED Credentialed Eating Disorder Clinicians.

References

Australian Government Department of Health and Aged Care (2026) Medicare Benefits Schedule (MBS) – fact sheet for people with eating disorders. Canberra: Australian Government Department of Health and Aged Care. Available at: health.gov.au/resources/publications/medicare-benefits-schedule-mbs-fact-sheet-for-people-with-eating-disorders (Accessed: 23 April 2026).  

Bratland-Sanda, S. and Sundgot-Borgen, J. (2013) ‘Eating disorders in athletes: Overview of prevalence, risk factors and recommendations for prevention and treatment’, European Journal of Sport Science, 13(5), pp. 499–508. doi:10.1080/17461391.2012.740504.  

Butterfly Foundation (2026) Support for eating disorders and body image. Sydney: Butterfly Foundation. Available at: butterfly.org.au/ (Accessed: 23 April 2026).  

Colangelo, J., Smith, A., Bitterlich, N., Buadze, A. and Liebrenz, M. (2025) ‘Risks for eating disorder in ultra-endurance athletes and the role of training volume: A cross-sectional study’, Frontiers in Sports and Active Living, 7, article 1708869. doi:10.3389/fspor.2025.1708869.  

InsideOut Institute (2023) Eating disorders: myths and misconceptions. Sydney: InsideOut Institute, University of Sydney.

Wells, K.R., Jeacocke, N.A., Appaneal, R., Smith, H.D., Vlahovich, N., Burke, L.M. and Hughes, D. (2020) ‘The Australian Institute of Sport (AIS) and National Eating Disorders Collaboration (NEDC) position statement on disordered eating in high performance sport’, British Journal of Sports Medicine, 54(21), pp. 1247–1258. doi:10.1136/bjsports-2019-101813.