Assert Fitness | Northumberland Fitness | Nutrition coaching | Group Training | Personal Training – Believe to Achieve

We Want To Help You Transform Your Body And Change Your Life

Experience the Assert Fitness difference and find out how guys and girls in Northumberland are losing weight, getting stronger, dropping jean sizes and feeling awesome with our affordable semi private and group training packages.

"When we can no longer change a situation, we are challenged to change ourselves." - Victor Frankl

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We are a premium fitness training facility based in West Sleekburn. Our modern studio has been designed to be a private environment for professionals and parents to prioritise their health & fitness.  Life is increasingly hectic but our membership programmes are designed with the busy client in mind.

Let us help you take back control of your health and fitness by creating long lasting and sustainable exercise and eating habits. Why waste time wandering around a gym wondering what to do next or going for that same run over and over again.  Let us take care of your exercise programming with our unique, fun, and varied sessions that get RESULTS. No stone has been left unturned in our quest for your success.

Our small but dedicated team exist to inspire and coach you towards reaching your true potential.  



We understand that you are busy. So we work hard to make our training systems the most impactful to fit into  your life in the shortest amount of time. Effective, Efficient and fun training. Nobody wants to spend 2 hours in the gym, when they could spend half of that and get double the results. We focus on helping you move better, move more freely and get stronger. Our Training Programs are designed to be short and effective and burn anywhere between 500-1000 kcals without slogging it out for hours on the treadmill or elliptical trainer. Training can and should be fun, effective and exciting. We aim to bring that to every session.



We’ll take your nutrition from where it is now & teach you the fundamentals of building individual nutrition frameworks based on our Foundation Nutrition habits. We educate our members to show you how to build these habits into your lifestyle long term. Nutrition can be overwhelming, there’s so many conflicting pieces of information. We’ll start where you are and give you a straight forward and direct plan tailored to your needs. You CAN absolutely get the results you desire without ever counting calories or being on a restrictive diet. We then progress you to a more advanced program to take your results to the next level.


Why don’t we call ourselves Personal Trainers? Truth is a Personal Trainer will do just that, give you a training program and a nutrition plan. Here’s where that falls short. We can give you the BEST Diet and Training program IN THE WORLD but if you’re unable to stick to it what’s the point. In our coaching we focus on helping you make switches to your lifestyle, meeting you where you are at and giving you a map to move forwards.  We understand that you may be stuck and so we help you release your brakes to success. Allowing you to make better choices and craft new habits. We focus on your transformation at your pace. 

We are a results driven Training & Performance centre. To allow you to perform at your best & get the results you desire is about training and having a nutritional framework & a community to support you to realise your goals.

Click the Button to book your FREE, no obligation transformation session