About | 4th Discipline

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.

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

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.

Research & Evidence

Evidence-led articles that examine current nutrition, health and performance research, challenge misleading headlines and explain what the science means in practice.

Explore the Science

The Business of Endurance

Conversations at the intersection of endurance sport, business and personal development. Co-hosted by Claire Fudge and Charlie Reading, the podcast brings together world-class athletes, sporting leaders, researchers, adventurers, business owners and entrepreneurs to explore what it really takes to pursue ambitious goals and sustain performance over time. Discover honest conversations about resilience, health, leadership, identity, setbacks, recovery and the lessons that endurance can teach us about business and life.

Listen to the Podcasts

Real Performance Stories

Case studies and client experiences showing how personalised nutrition and Personal Performance Precision have supported meaningful improvements in energy, health, recovery and performance from the podium to boardroom and beyond

Read the Stories

The Performance Pulse

A practical newsletter bringing together current research, performance nutrition insights and clear takeaways for athletes and driven professionals.

Read the Newsletter

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.

~ Richard CFO and Ironman Age Group Athlete

“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”

~ Toni Director and Triathlete

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!

~ Claire Business professional and Ironman triathlete

“ 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”

~ Seanin Law professional and Triathlete

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

~ Anonymous Business professional

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 the past few months and I would definitely seek her advice in the future.

~ S Business Professional

Thank you for your help over the last few months. It was very helpful and I learnt many things I was not aware of before.

~ Giulia Runner

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” . –

~ Morgan Pearson Professional Triathlete USA and Double Olympic Silver Medalist

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.

~ Sabrina Stadelmann Economist and Professional Swiss Triathlete

training for my first Ironman I knew how important getting my nutrition right would be leading up to the race and on race day. Claire has helped me more than I could have imagined. Lifestyle changes we have discussed and implemented have meant that unlike any fad diets before; I am leaner and letting my food be the proper energy and recovery source it should be. Claire is always supportive, really cares about the people she works with and I love her approach to nutrition; working with what you have to make the best out of your body.

~ Vicki Business professional and Triathlete

“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 “

~ Caroline Business professional and Triathlete

“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”

~ Andrew Managing director and Triathlete

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

~ Jeffrey

“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”

~ Jordan Triathlete

“I run better, I feel better, I’m not getting injured, and I sleep well”. “I thought I needed a diet plan; but that is exactly what I didn’t need. I gained the knowledge and support and the balancing of everyday life around training along with personal life too”.

~ Sam Lt Cdr Thompson MBE RN, Senior Naval Instructor Wildcat Training Centre, and Ironman Age Group Triathlete

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.

~ Joanne Managing Director and Athlete

A big thank you for helping me to manage my eathing regime. Meal advice before the race seemed to really help keep my stomach settled on race day. I was very pleased with my race results. Really impressed by how good I feel and not so tired. A lot of this has to do with my new meal plans for training and racing.

~ Anne Athlete

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.

~ Kevin

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!

~ Jen Psychologist and Yoga

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

~ Steph Runner

“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”

~ Ella Runner

“swam my fastest 100m since I stopped competitive swimming as a kid…. I am feeling great”

~ Marti Business professional and Swimmer

“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”

~ Charmaine Business professional

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.

~ Giles C. Finance Director – Retired and Ironman Age Group Athlete

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.”

~ Rachel Managing director and World-class triathlete

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.

~ Laura Business Tech Marketing Professional and Athlete

I first met Claire Fudge of 4th Discipline in the summer of 2021 for sweat rate test to better understand his electrolyte and hydration requirements for training for a Guinness World Record attempt for an endurance event.
I came away thinking I would like to work with the 4thdiscipline team as they provide nutrition coaching for performance to professional athletes and people like me who have been blundering through the nutritional needs of heavy training.
4thdiscipline know their stuff and their engagement with me was focussed on my individual needs basing my education and planning on science. At all times they worked with me in a calm, supportive and realistic fashion.
For anyone looking to improve their understanding and knowledge of food and sport I can highly recommend them!

~ Seamus IT consultant and Squash

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.

~ Jess Doctor and World-class Ironman athlete

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.

~ Allysha Krall Triathlon Coach and USA Pro Triathlete

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.

~ Penny Teacher and Triathlete and cyclist

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.

~ Laura Siddall Professional British Triathlete

“ 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”

~ Mary R. Doctor and Ironman Age Group triathlete and Endurance Athlete

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.

~ Heather Teacher and Age Group Triathlete

Struggling with allergies, intolerenaces and anxiety around food for many years had a huge umpact in my daily life, being able to properly fuel for marathon training, recovery and race days. Symptoms have improved dramatically, my training is much more efficient and my confiedence around food has grown. I have lost count of the different diets and plans that I have tried; I have seen a really positive change. I really couldn’t recommend Claire any more highly.

~ Rhys Accountant and Marathon runner

“ 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”

~ Sophie Physiotherapist and GB pole vaulter

Which service is right for me?

Do you only work with professional and elite athletes?

What is Personal Performance Precision?

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.

What is the difference between a dietitian, a nutritionist and a nutritional therapist?

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.

Do you work with people with eating disorders or REDs?

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.

Do you write meal plans or diet plans?

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.

Do you offer one-off consultations?

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.

What happens after I enquire?

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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Science-Led.
Personally Engineered.

My Story

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