Science-Led.
Personally Engineered.

Claire Fudge | Clinical Director
Registered Clinical Dietitian • Registered High-Performance Nutritionist
Endurance Athlete • Award-Winning Speaker
BSc (Hons) Nutrition & Dietetics • PgCert Sport & Exercise Nutrition, Adv.Dip
Personal. Performance. Precision.
Clinical insight, performance science and more than 23 years of experience, translated into nutrition strategies engineered around the individual.
My Story
Long before I understood the science of nutrition, I understood the passion that goes into food. Raised in rural Dorset within a family bakery spanning three generations, I remember packing gingerbread men destined for Harrods and watching simple ingredients become something people valued and enjoyed.
That early connection with food led me to train as a Dietitian at King’s College London. My clinical career took me into intensive care, trauma, gastroenterology, oncology and eating disorders, where I saw that nutrition was connected not only to food, but to healing, function, social connection and quality of life.
Alongside this, I was building a career, running a business and competing as an endurance athlete. After more than 17 Ironman races and competing at World Championship level, I understood first-hand the challenge of fuelling, recovering and staying healthy when life is demanding.
I created 4th Discipline to connect clinical nutrition, performance science and real life.
Today, I combine more than 23 years of experience with data, evidence and lived experience to support people in building the health, energy and resilience to perform now and for years to come.
The Story Behind 4th Discipline
In this conversation with Charlie Reading, I share the journey behind 4th Discipline and why health and performance should never be treated as separate goals.
What Happens When the Drive to Perform Exceeds the Capacity to Recover?
A racing car performs at its best because every system is monitored, fuelled and adjusted before small issues begin to affect performance. The body is no different.
For many partners, business owners, professionals and athletes, the signs may slowly appear : meals may become irregular, caffeine and quick fixes often fill the gaps, concentration and clarity fade so there may be less physical and mental capacity left for training, family or recovery.
Training may begin to feel harder than expected, recovery may take longer, body composition may become more difficult to manage, or persistent symptoms and health may quietly become accepted as normal.
At the same time, an overwhelming stream of books, podcasts, social-media advice and competing health claims can make it difficult to know what is credible, who to trust or which strategy is personally relevant.
The truth is that most solutions only scratch the surface. Generic advice rarely connects the factors influencing clarity, recovery, training, body composition and long-term health.
At 4th Discipline, the approach is different: we analyse the full picture, separate evidence from noise and uncover the underlying issues before building the right personalised strategy.
At 4th Discipline, the focus is not simply on nutrition plans or short-term outcomes. We examine the full picture to understand how nutrition, health, training, recovery, sleep, stress and lifestyle are interacting before creating a personal strategy.
Founded and led by Claire Fudge, a Clinical Dietitian, High-Performance Nutritionist and endurance athlete with more than 23 years of experience across clinical practice and elite, Olympic and professional sport, our team brings together evidence, clinical expertise and real-world performance experience.
Imagine If You Could:
- Understand what is really affecting health, recovery and performance
- Sustain clearer thinking and concentration across demanding working days
- Maintain greater physical and mental capacity for work, family and training
- Improve sleep, recovery and readiness to perform
- Arrive at training better fuelled and able to adapt more effectively
- Improve body composition without rigid rules or unnecessary restriction
- Identify patterns behind persistent symptoms, health concerns and biomarkers
- Make more informed decisions about nutrition, supplements and emerging trends
- Recover more predictably between demanding sessions and events
- Build practical habits that support work, life, training and long-term health
This is Personal. Performance. Precision. Science, clinical expertise and high-performance experience translated into practical action for real life.
Our Guiding Principles
The person comes first. Evidence provides the foundation. Experience guides the decisions. Science is translated into action.
Human First. Always Individual.
Performance and health are deeply personal. Research, data, equations and clinical guidelines provide valuable direction, but no individual is truly “textbook”.
Each person responds differently according to their health, physiology, lifestyle, training demands, environment, stress, recovery and personal circumstances.
That is why, at 4th Discipline, we take time to understand the whole person, not simply their symptoms, diet or performance goal.
Every strategy is shaped around the individual and designed to work within their real life.
Evidence-Led. Fact, Not Fiction.
Nutrition is crowded with conflicting advice, bold claims, trends and pseudoscience.
It can be difficult to know what is credible, what is relevant and what should be ignored.
Led by Claire Fudge, a Registered Clinical Dietitian and Registered High-Performance Nutritionist, 4th Discipline uses current research, clinical reasoning and performance science to guide every recommendation.
Evidence provides the foundation.
It enables informed decisions to be made without relying on generic advice, restrictive rules or the latest trend.
Experience Guides Decisions.
Science helps establish what may work.
Experience helps determine what is most appropriate for the individual, at the right time and in the right context.
More than 23 years across clinical dietetics, elite and world-class sport, research and endurance competition have shaped the way 4th Discipline approaches nutrition, health and performance.
It requires an understanding of how health, training, recovery, lifestyle and behaviour interact.
Experience supports better questions, clearer decisions and more precise strategies.
Science Translated Into Practice.
Knowledge only creates change when it can be applied.
The most scientifically accurate recommendation still has limited value if it cannot be implemented within the realities of work, training, travel, family life, medical needs and personal preferences. Experience bridges the gap between theory and practice.
At 4th Discipline, complex evidence is translated into clear, realistic strategies that can be used, evaluated and adapted in real life.
The aim is not to simplify the science or replace it with opinion. It is to apply it intelligently and create meaningful, sustainable change.
Ready to Discover What Is Possible?
Whether you are an athlete pursuing the podium, a business professional managing persistent symptoms, or looking to strengthen your health and capacity to perform, the next step begins with understanding what matters most.
Evidence Translated into Better Decisions
Explore science-led articles, expert conversations with athletes and leaders and real-world case studies exploring nutrition, clinical health, endurance and human performance. Each resource cuts through headlines and trends to explain what the evidence means, where its limitations lie and how it can be applied in practice.

Research & Evidence

The Business of Endurance

Real Performance Stories

The Performance Pulse





I went to visit Claire for a sweat test. This was really useful and informative experience and Claire is very knowledgeable and helpful.





I had a sweat test done by Claire – I’ve yet to put the results into practice, but really enjoyed our discussion. She explained the process and how to put the results into practice very clearly. She also seemed to me to have a very balanced view (it was not just a sales pitch for Precision Hydration!) which gave me a lot of confidence in her advice.





claire challenged my unhealthy food beliefs in an empathic manner and suggested changes that were specific and achievable whilst continuing in my recovery from anorexia. “her knowledge and support have been really valuable in the progress I have made over





Since working with Claire, she’s made a huge difference to the way that I’ve been able to execute my training sessions, bring the energy that I need at the right times to competition, and get the most out of recovery. I wholly recommend giving Claire a call. The biggest thing to take away is that everything that we do is absolutely manageable!





“have really appreciated the holistic approach to your guidance that reflects a genuine desire to teach me the skills I need to become the healthiest and strongest athlete I can be”





“You quite literally changed my life; I could not have done this without you”





Where I’ve really benefited from working with Claire Fudge is around the timing of food around my training, but also particularly around travel. Working with Claire on a plan so that I don’t go for chocolate in the airport or at the petrol station, but have snacks and planned timing along the way has really been beneficial. She’s great at delivering helpful tips that are quick and easy to do.





I’ve learned so much stuff I didn’t even know existed, different types of proteins, when to take, when to take dairy, how to stay full, what’s a good probiotic to boost my immune system…I’m always learning, I think I’ve really improved” . –





instrumental in uncovering my coeliac disease, supporting me to make the necessary changes to a gluten-free lifestyle, which alleviated by IBS symptoms. This in turn positively impacted my fertility. Can’t thank her enough for her tailored expertise which also extended to advice around diabetes management during pregnancy!





“Your encouragement means a lot at a time when work and training is difficult and I cannot see the journey back to ‘normal’….. your positivity is highly contagious – I feel better already “





I started working with Claire when I realised that I thought I knew what I was doing but I really didn’t when it came to sports nutrition. I’d been competing at an age group level internationally in triathlon and since working together, my performances have improved together with making podium places as well as making the jump up to 70.3 a successful one.





I cam to see Claire in the run-up to my first ironman event. Within days of following her advice, I saw a noticeable difference; Training is improving all the time. All is on track for nailing the nitrition for the ironman event next month!





In Claire, I have found a dietitian who not only is a specialist in nutrition, but also really understands the specific demands of an athlete. She acknowledges that one size does not fit all and really considers all the different aspects in optimizing nutrition for me as an individual. Most importantly, she helps me understand every little step of the process so that I know how to fuel myself even when she’s not around.





“I could start to eat intuitively again; I recovered my menstrual cycle and eat intuitively without any fear; she was there with support and guidance”





“exceptionally supportive …excellent knowledge of nutrition both in terms of supporting sports performance but also in optimising health. Claire’s background in long distance triathlon herself means that she is able to support in ways others wouldn’t …..her race and training experiences. I (would) recommend Claire for anyone who is looking for support with their nutrition – either for optimising everyday health and wellness or for enhancing and supporting sports performance”





I have worked with Claire for over a year having suffered with disordered eating from an early age. I knew I needed to do something to change it.





I went to Claire looking for a quick fix, however Claire explained in detail the process and why I needed to take a different approach to hit my goals. Claire was very encouraging, providing weekly support and further analysis on my progress.





“ Claire went into a lot of detail, preparing nutrition plans for me and for ½ and full races and also assisted me with recovery nutrition. She is very supportive and knowledgeable. I would highly recommend her”





I really enjoyed the discussions with Claire. She gave me really good and relevant advice which helped me a lot to overcome my problem.





“revolutionised how I eat during …. big sessions. From my former race snacks mindset to a proper fuelling strategy-it’s made a demonstrable difference in my form”





When I started nutrition coaching with Claire I’ve saw an absolutely incredible difference in not only my racing performance and day to day training, but a difference in my everyday life. It has changed how I perceive food and how I think about myself and how I can best fuel myself for what I have to do that day.





“before my first 70.3 …we identified my intolerances for everyday life, (she helped) fuel my training sessions and put together a plan for the lead up to my race and race day itself. “Claire being a triathlete herself, her advice is second to none”





Just wanted to email you with a big thank you for helping me to manage my eating regime. I was very pleased with my race results.





“helped me relearn that “Food is food”.Fed up of seeing zero results through yo-yo dieting, I had tried intermittent fasting, Keto and various other diets. I wanted a lifestyle change and wanted to be able to enjoy food without the guilt associated with “bad food”. I can now enjoy eating fruit without feeling guilty! I’m confident I will reach my goal weight comfortably and remain constant”





I’ve been running for quite a few years, but I just kept running out of energy. Training for a marathon, I got in touch with Claire. I thought she would just give me a food plan, but she basically educated me on what I needed to eat and the right food groups to eat together. It was just an absolute game changer. I did my marathon with absolutely no problems—didn’t once run out of energy.





I was a relatively competitive athlete but wasn’t getting any better. My relationship with food was challenged, but Claire Fudge unzipped all of my psychological hang-ups and addressed it with science. It freed me from worrying, and I actually started enjoying food again. It’s an educational investment, a change-in-whole approach, and something I will carry through for life. I can’t recommend her highly enough.





I wanted to understand what food is good for me as I trained and when doing races…..some foods did not agree with me but I did not understand why……..Gave me these answers and has helped me improve my race times as well as eat more sensibly. My lifestyle has benefited from this enormously. I received expert advice on what to eat during (injury) ….incredibly helpful and informative and I was impressed at her wealth of knowledge & experience. “Claire helped me understand what foods work for my body. I’ve improved my race times and transformed my lifestyle.”





The work we have done together has covered race day nutrition, everyday nutrition, and has helped me have a better relationship with food. So often we have coaches for the sports we do, yet no guidance or coaching when it comes to nutrition. Working with Claire has really helped up my performance. Thanks to Claire and Fourth Discipline for all the continued support.





A friend who is a no nonsense athlete was working with Claire and I thought she would be good for me as although not a ‘real’ athlete myself, I wanted to understand how to fuel for 70.3 training and simultaneously sort out my ongoing chaotic relationship with food and eating for ‘normal life’. I knew Claire had an understanding of and worked in both areas.





I felt at the time when I started with Claire that the quality of my life wasn’t very high and I was really struggling to enjoy my training. I certainly wasn’t enjoying food and it’s safe to say that she worked with me every step of the way to transform my life everyday.





Just wanted to email you with a big thank you for helping me to manage my eating regime. I was very pleased with my race results.





“ frankly i hadn’t got any knowledge….Claire was amazing! She helped me plan out my nutrition… to make sure i was getting the best performance (this) allowed me to fully concentrate on the competition.. “best competitive season of my life so far, gaining my first GB senior vest competing at the Athletics World Cup, 2nd place at the British Championships and becoming England Champion gaining my first England Senior International vest”





“Claire’s methods didn’t leave me feeling hungry or depleted of energy like fad diets can, in fact I couldn’t quite understand how I was able to eat quite so much and feel so full and strong………what a difference having a nutrition plan to work with made. My performance rocketed and I completed my two dreams in one season. Medalling at the European Middle Distance AG triathlon and smashing my first ironman”





“ I could write so much more . Claire has done an amazing job, and been great, provided consistent, caring support along a tough path to improve my nutrition and expert, individualised advice for fuelling (…) Claire is so well informed, not only in sports nutrition and supplements but also (…) in other areas, including sleep; protein, and ageing (in the context of) a healthy balanced nutritious diet to meet daily and training needs. I have learnt so much and feel so much more equipped to fuel”





Great first meeting and assessment with Claire. A huge amount to take in but Claire guided me through the first stage. Have some clear first steps to work on in my journey to improving my hydration and nutrition to support improved training and race performances.
Frequently Asked Questions
The right service depends on whether you are looking for support as a driven professional, a professional who competes, an athlete, a team, a research organisation or an event organiser.
If you are unsure where to begin, book a discovery call and we will guide you towards the most appropriate pathway.
No. I work with professional and Olympic-level athletes, athletes on talent and high-performance pathways, competitive age-group athletes and professionals who train, race or compete alongside demanding careers.
The level at which you compete is less important than your commitment to improving your health, fuelling and performance.
I also support driven professionals who are not athletes but want to improve their energy, focus, resilience and long-term health.
Personal Performance Precision is my approach to creating nutrition support that is fit for purpose and designed around the individual.
Generic plans are built for an average person. They do not account for your physiology, health history, symptoms, training, workload, lifestyle, preferences or goals.
Personal Performance Precision brings these factors together with clinical expertise, performance science and meaningful personal data. This allows us to identify what is affecting your health and performance, then engineer a practical strategy around your specific needs.
Like a tailored suit rather than something taken straight from the rack, the strategy is shaped around you: how you live, how you move, what your body needs and what you are working towards.
The result is not simply more nutrition information. It is a clear, personalised approach designed to support your energy, health, recovery and performance now and over the longer term.
In the UK, dietitian is a legally protected title. Dietitians are regulated healthcare professionals qualified to assess and treat nutritional problems, including those associated with medical conditions.
The titles nutritionist and nutritional therapist are not legally protected, so qualifications, training and experience can vary. Registered Nutritionists and nutritional therapists who belong to recognised professional bodies may have completed relevant training, but their scope of practice differs from that of a registered dietitian.
As a Registered Clinical Dietitian and High-Performance Nutritionist, I combine clinical assessment and evidence-based care with specialist sports and performance nutrition.
This is particularly important where symptoms, blood markers, low energy availability, gut issues, injury, REDs, disordered eating or a medical condition may be affecting health and performance.
Yes. I provide specialist clinical and performance nutrition support for athletes and active individuals with eating disorders, disordered eating, Relative Energy Deficiency in Sport (REDs) and low energy availability.
Support may include nutritional rehabilitation, restoring adequate fuelling, reducing nutrition-related risk, supporting training and recovery, and working alongside doctors, psychologists, physiotherapists, coaches and other members of the multidisciplinary team where appropriate.
Where clinical risk is present, the priority is always safe, coordinated and appropriate care.
A clear plan for what, when and how you eat can be valuable, but lasting change requires more than a prescriptive meal plan.
Where appropriate, I provide personalised meal structures, fuelling plans, practical food ideas, competition strategies and guidance around timing, recovery and preparation.
These sit within a wider approach that considers your health, schedule, training, travel, preferences, symptoms and goals.
The aim is to give you a strategy you can understand, adapt and sustain rather than a rigid plan that only works temporarily.
Most individual support is delivered through a structured programme rather than a single appointment.
A first consultation begins the process of understanding your symptoms, patterns, data, health history, training demands and goals. Follow-up support allows recommendations to be implemented, reviewed and refined.
One-off specialist consultations may be available for clearly defined needs, such as an expert review or sweat sodium testing.
Please contact the team to discuss the most appropriate option.
You will be guided towards the service that best matches your goals, health needs and performance demands.
Where appropriate, the first step will be a discovery call or initial conversation to understand the support you are looking for and whether the service is the right fit.
You will then receive clear information about the recommended pathway, what is included, the expected timescale and the investment required.
A limited number of new clients are accepted each month to maintain the depth and quality of personalised support.
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