Race results

Recent race results include;

1st Team Southwater Triathlon Relays 2012

1st Worthing Sprint Triathlon 2012

1st Ashburnham Sprint Tri 2012

4th European Olympic Distance Triathlon Championships 2012

1st Dorney Sprint Triathlon Beijing Qualifier 2011

1st Eton Supersprint triathlon 2011

3rd Windsor Olympic triathlon 2011

2nd Bala Olympic Triathlon 2011

2nd Saucony 10k run 2011

Serpentine RC Middle Distance Multisports champion 2011

3rd Vitruvian Middle Distance Triathlon 2011

1st London Triathlon (Olympic Plus) 2010

Qualifications/ Professional Affiliations:

YMCA Level 3 Personal Trainer

YMCA Level 2 Gym Instructor

STA Level 2 Award in Swim Teaching

Edexcel Level 2 Certificate in Sport

British Triathlon Coach Level 1

England Athletics Run Leader

CTUK Cycle Coach

Register of Exercise Professionals Member (REP) No. R0082457

Swimming Teachers’ Association (STA) Associate Member No.165609

Triathlon England (BTF) Member No. E1031441

fitso fitness

fitso fitness elliptigo traing brighton & hove

Marianne Clark

Marianne is a Level 3 Personal Trainer with a lifelong passion for sport and fitness. She is also a qualified triathlon and run coach, cycle instructor and swimming teacher.

Marianne is currently one of the top UK female age group triathletes, competing at all distances from supersprint to half ironman distance. In 2011 she qualified to represent GB age group team at the World Triathlon Championships in Beijing and in 2012 finished 4th at the European Triathlon Championships in Israel and qualified to race at the 2013 European Championships in Turkey.


I was a lawyer for many years working for high profile individuals in the film, tv and music industries, but it never gave me the energy, passion, fun, and unrivalled sense of achievement that sport and fitness has consistently given me over the years.

People underestimate all the positives an active lifestyle can bring; it’s not only about a healthy body, it’s about confidence, personal challenges, well-being, and fulfilment and so much more. It gives me immense satisfaction to help others enjoy those same benefits”


Marianne has always been involved in sport since her school days when she played squash and tennis at county level.

After university she became a regular recreational runner and cyclist.

Over the past 10 years Marianne has become particularly interested in endurance sports and multisports and she is currently one of the top female age group triathletes in the UK. She competes at all distances from supersprint to half ironman distance, regularly achieving podium finishes.

Marianne also competes in duathlon and in single sport endurance events including open-water swimming, road cycling and distance running. She has a sub 4 hour marathon to her credit, and a 1.40 half marathon. As well as being a personal trainer, Marianne is an England Athletics Run Leader, a British Triathlon Coach, a CTUK Cycle Instructor, STA swimming teacher and one of the UK’s only ElliptiGO trainers.

Marianne has trained numerous runners, cyclists and triathletes to success, and has run fitness groups for adults and children in London and Brighton.

Fitso Fitness can help you with the following:

fitso fitness brighton and hove 1-2-1 Personal Training

  • fitso fitness brighton and hove Group Fitness Training

fitso fitness brighton and hove Swim – Bike –Run - Triathlon Training

fitso fitness brighton and hove On-line training plans

fitso fitness brighton and hove General Fitness Testing

fitso fitness brighton and hove Advice on nutrition, equipment, events

Triathlon Coaching

Marianne can help with all aspects of triathlon training, from improving endurance techniques to diet and mental attitude. Click here for Triathlon information.

With a wealth of knowledge and experience, Marianne can help you in completing every aspect of your triathlon programme. Click here for Triathlon information.




Call us for more information on 07775 780844 or check out our current classes on our live timetable: