The Female Athlete: A Masterclass in Sports Nutrition and High Performance
A Conversation with Dani Di Francesco, Eva Goodisson, and Michelle
Buchegger
In the world of high performance, the conversation around athlete nutrition is shifting. For decades, the industry relied on data derived primarily from male physiological profiles, often leaving female athletes to navigate a landscape of misinformation. This deep-dive interview features Dani Di Francesco, an Accredited Practising Dietitian; Eva Goodisson, an elite triathlete and Olympic contender; and Michelle Buchegger, co-founder of Fixx Nutrition. Together, they unpack the complexities of the female body, the dangers of RED-S, and the essential strategies for fuelling success in endurance and trail running.
Redefining the Standard: What is RED-S?
Michelle Buchegger: Dani, you’ve been an incredible advocate for better
education in the sports nutrition space. One term that keeps coming up in professional circles but remains a mystery to many amateur athletes is RED-S. Can you define that for us and explain why it is so critical for female health?
Dani Di Francesco: Absolutely. RED-S stands for Relative Energy Deficiency in Sport. It is a condition that occurs when an athlete’s energy intake is insufficient to support both the physiological demands of their training and the basic functions required for health and daily living.
It used to be known as the 'Female Athlete Triad', but it has since evolved into a much broader umbrella term. When you aren't fuelling adequately, your Resting Metabolic Rate (RMR) drops. This is your body’s baseline energy requirement just to keep your heart beating and organs functioning at rest. When that energy isn't there, the body starts shutting down non-essential systems. We see it manifest in bone turnover issues, endocrine disruption, and a severely weakened immune system. While research is growing, it’s still not talked about enough in the high-performance world.
The Weight of Expectation: Thinner vs. Faster
Michelle Buchegger: Eva, you have been competing at an elite level for nearly a decade. How have you seen this play out on the ground, particularly during your time in the US college system?
Eva Goodisson: I remember being 17 and heading to the US on a scholarship. The culture back then was very much 'thinner is faster.' I remember a recruiting trip where a coach told me, 'We don't really eat carbohydrates here.' Looking back, that is absolute madness for an endurance athlete. Carbohydrates are your primary source of fuel.
When you’re young and ambitious, you do what you’re told. I followed that low-carb, low-calorie advice, and it led to a cascade of injuries. It’s quite sad to think about now - how much better could I have been if I had been fuelling my body properly? I eventually learned that as a female endurance athlete, it is almost impossible to'over-fuel' because the training volume is so high. Your body just burns through it. Once I prioritised athlete nutrition, I found I could achieve so much more.
Michelle Buchegger: It’s a common story. Dani, you had a similar experience coming from a professional swimming background, didn't you?
Dani Di Francesco: Exactly. My coach was very 'old school.' We had our skinfolds measured every month, and there were often remarks made about our body profiles that didn't make us feel great. As an athlete, you often have a level of perfectionism or OCD, so you take those tendencies to extremes. I was swimming 80km a week and cutting out carbs - the very thing I needed. I was constantly sick. It was only through my studies that I realised the damage I was doing. Now, in my clinic, I’d say 99% of my clients are under-fuelling, and most of them are doing it unintentionally.
The Science of the "Unlock" Electrolytes and Hydration
Michelle Buchegger: My own journey was slightly different. I train to maintain fitness, then ramp up when an event like the Chicago Marathon or a major trail-running race comes along. The big 'unlock' for me was when we developed Fuel X.
Before that, I would arrive at work after a morning session feeling completely depleted. Once I started using Fuel X, which combines electrolytes and carbohydrates, I noticed a massive shift. I could get through the work day without that 3 p.m. crash.
Dani Di Francesco: That’s a vital point, Michelle. For women, fuelling isn't just about the race; it's about the recovery and daily function. Why do you think products like Fuel X Pro or our CrampFix range have become such staples for the endurance community?
Michelle Buchegger: It comes down to simplicity and gut comfort. For endurance athletes, especially in trail running, you are out there for hours. If your nutrition strategy is off, or if you start cramping, your race is over. CrampFix works through the neuro-muscular system to stop cramps in seconds, while Fuel X Pro provides that steady stream of energy and hydration. For women specifically, having a clean, palatable fuel source that doesn't cause GI distress is a game-changer.
Physiological Divergence: Why Women Are Different
Michelle Buchegger: Dani, let's talk physiology. We know men and women have different muscle mass and hormone levels, but how does that translate into specific sports nutrition requirements?
Dani Di Francesco: We are significantly different. For starters, a woman’s iron requirements are roughly double those of a man. We lose iron through the menstrual cycle, as well as through sweat and microtears in the muscles during heavy training.
Then there is Oestrogen. Oestrogen is critical for bone health because it inhibits the breakdown of bone tissue. If you are under-fuelling, your oestrogen levels drop. This disrupts the balance between osteoblasts (bone builders) and osteoclasts (bone breakers). This is why so many female athletes suffer from stress fractures.
Eva Goodisson: That was exactly my experience. I had three stress fractures in my left foot during college. I also didn't have a menstrual cycle for three years. It was a direct correlation. It wasn't until I had a 'lightbulb moment'and realised that to get to the Olympics, I had to be healthy. I certainly had my struggles getting my cycle back but I feel so much stronger, resilient and energized, as well as less injury prone and achieving better results compared to when I didn’t have it.
The Dangers of Fasting and the Cortisol Trap
Michelle Buchegger: One trend that I see a lot of people talking about is intermittent fasting. Dani, what is your professional take on this for female athletes?
Dani Di Francesco: It is a big 'no-no' for most women in high performance. Women are much more sensitive to energy changes than men because of the way oestrogen and cortisol interact.
Fasting can spike cortisol levels, putting the body in a state of stress. This can
suppress reproductive hormones and slow metabolism, exactly the opposite of what an athlete wants. While some men might tolerate it, for women, it often leads straight back to that low energy availability bracket. I always recommend fuelling before, during, and after training to keep the body's systems running smoothly.
Practical Strategies for Trail Running and Endurance
Michelle Buchegger: I’ve noticed that as I’ve gotten older, my running has been 'going downhill' because I've been getting weaker. I’ve had to ramp up strength training and Pilates, but I’ve also had to be much more focused on my fuelling during long trail runs. If I go off track during a four-hour run, I am sluggish and dehydrated the next day.
Eva Goodisson: I think being organised is the biggest factor. When I was younger, I’d finish training and not eat for two hours because I was busy or socialising. Now, I have my recovery protein ready to go. You have to be proactive. If you’re doing the work, you have to give your body the tools to repair.
Dani Di Francesco: Exactly. And it’s about the quality of those tools. Michelle, you’ve always been big on 'clean' ingredients. How does that play into the Fixx Nutrition philosophy?
Michelle Buchegger: It’s everything. There is so much 'nasty stuff' in processed sports foods—artificial flavours and chemicals that can wreak havoc on your gut and hormones. We focus on natural, high-quality ingredients because when you’re pushing your body to the limit in an endurance event, the last thing you need is a chemical cocktail causing inflammation.
Final Tips: Building a Sustainable Path
Michelle Buchegger: To wrap up, what is one piece of advice you would give to women looking to improve their athletic nutrition?
Eva Goodisson: Keep it simple. Don't overcomplicate it with every new fad. Stick to balanced meals and ensure you are eating enough for the work you are doing. If you are an endurance athlete, keep those carbs coming in. They are your best friend.
Dani Di Francesco: Listen to your body. If you are getting recurrent illnesses, feeling constantly fatigued, or suffering from bone injuries, it’s a sign your fuelling is off. Don't guess-speak to an accredited dietitian. We can help you create a plan that aligns your intake with your output so you can actually reach your full potential.
Michelle Buchegger: And from my side, don't ignore hydration and recovery. Whether it’s using Fuel X Pro during your run or a high-quality protein afterwards, those small habits are what allow you to back up day after day.
Thank you, Dani and Eva. This has been an incredible deep dive into the needs of the female athlete. We look forward to sharing more of this in our upcoming ebook.
Key Takeaways for Your Nutrition Strategy:
- Prioritise Carbs: They are the primary fuel source for high-intensity and
endurance work.
- Monitor Menstrual Health: A missing period is a major red flag for RED-
S. - Clean Fuel: Use products like Fuel X and CrampFix to manage
electrolytes and prevent performance-ending cramps without artificial
additives. - Strength is Key: As we age, maintaining muscle mass through strength
training and protein intake supports metabolism.