Expert coaching. Supportive community. Real results. Grand Union CrossFit is a welcoming gym in Berkhamsted, Hertfordshire – whether you're looking to lose weight, build strength, improve your fitness or simply feel better day-to-day, we're here to help, whatever your age, level or experience.
YOU'RE IN THE RIGHT PLACE FOR…
At Grand Union CrossFit, we help everyday people achieve extraordinary results through expert coaching, personalised guidance and a supportive community.
Structured programming and coaching that helps you build habits that last – not a two-week transformation gimmick.
Every movement is taught, scaled and progressed by a qualified coach. You'll leave stronger than you arrived.
Fitness that carries into work, family and everything else you love doing.
Small classes, accountable friends and social events that keep you coming back.
How it works
No workout. No pressure. Just a friendly conversation with a coach about your goals.
Three private 1-to-1 sessions to teach you the fundamentals, plus a 3-class-per-week membership, GU tee and your own skipping rope.
Step into classes with confidence – surrounded by people who've been exactly where you are.
Classes
60 min
Constantly varied, functional, high intensity.
1-to-1
The perfect way to start your CrossFit journey.
60 min
High intensity. Non-technical. A lot of fun.
60 min
Snatch. Clean. Jerk.
60 min
Strength for life.
60 min
Strong, confident, capable young athletes.
60 min
Own your bodyweight.
60 min
One-to-one or small group, on your goals.
Memberships
Pick the plan that fits your week – change, pause or cancel any time.
Get started
Most popular
Best value
Meet the team
Rob and Jenna have built Grand Union with bespoke classes and a friendly-but-firm coaching style. Wendy leads our Kids & Teens programmes.
Owner · Head Coach
CrossFit Level 3 · MSc Sports Medicine · BSc Sports Therapy
I've always been passionate about exercise, competing in a range of sports for as long as I can remember – from football and athletics to CrossFit and Ironman Triathlon. At university I specialised in injuries within sport, gaining first-class honours in Sports Therapy and a Masters in Sports Medicine at Exeter. Working in an injury clinic is where I found CrossFit, and my love for strength and conditioning grew from there. I began coaching in 2014, gaining experience across four different gyms before opening Grand Union CrossFit in my home town.
Co-Owner · Head of Community
CrossFit Level 2 · Gymnastics Level 1
I've always participated in sports and developed a natural competitiveness when I found a talent in athletics – I was a sprinter, competing at County and National level, until a bad injury stopped my potential career going further. I did what I could to keep fit and active – gyms, classes, running – but I found it hard to stay motivated and wasn't seeing the results I wanted. In 2016 I got roped into trying CrossFit and have been hooked ever since. I fell in love with the community first, then the training, and realised it was the lifestyle change I needed. I've since competed at a number of high-level competitions and developed my 1:1 PT and online coaching alongside coaching at GU.
CrossFit Kids Coach
CrossFit Level 1 Trainer · CrossFit Kids Certified
Hi, I'm Wendy! As a CrossFit Level 1 Trainer certified to train children and teens, I specialise in delivering safe, scalable and effective workouts. I'm a firm believer in fun, friendly and goal-orientated sessions for all – that build confidence, not just in the gym, but in everyday environments too.
Member stories
“Best gym I've ever been to. Rob and Jenna are amazing coaches – their focus on technique and doing things the right way is part of who they are. Never did I think I'd be learning (and absolutely loving) kipping pull-ups and Olympic weightlifting. Grateful to be part of the community at GU.”
“Joining as a complete beginner I was nervous, but that soon dissipated and my confidence grew quickly. The coaching is brilliant – huge knowledge, endless encouragement and lots of focus on technique. I'm now doing movements I never thought I'd be able to do. So wish I'd joined sooner!”
“I LOVE it here. My strength and fitness have improved a ridiculous amount and I'm so much more confident and happy in my body than when I started. Rob and Jenna have pushed me to do things I never would have attempted before. The small classes mean workouts can be adapted for all abilities – it really is such an inclusive place.”
“Jen and Rob are fantastic coaches and because the classes are small it feels like you're getting personal training. I joined around a year ago as a complete beginner and was made to feel really welcome. I'm feeling much fitter and stronger – best gym I've ever been to.”
“Grand Union CrossFit is life-changing. Whilst CrossFit can appear intimidating, GU really does offer training for all abilities. Rob and Jenna fully support you to use different scales and reach your own personal best. I've tried many local gyms and never found coaching at the level GU offers.”
“Absolutely the best gym in Berko town. Jenna and Rob push you hard but in a comfortable way. I'm running faster and pushing harder than I ever have – and most importantly, the music is great and everyone is so friendly!”
Inside a session
Coached from start to finish, scaled to you, and done alongside people who want you to succeed.
Community
The workouts are what get you in the door. The people are why you stay.
Knowledge Hub
Practical articles on training, nutrition and recovery from our coaching team.
Heading off for two weeks? Here's what actually happens to your strength, fitness and mindset when you step away from the gym – and why your first session back always feels harder than it is.
Rob Lang · 18 August 2026
With Embr opening in Berkhamsted, there's suddenly a lot more conversation around ice baths, saunas and recovery.
Rob Lang · 2 August 2026
Cut through the noise. A practical guide to protein targets, timing and simple ways to hit them without weighing every meal.
Jenna Nicholls · 18 June 2026
Ready when you are
A free No Sweat Intro with a coach. No pressure. No commitment. Just a genuinely useful conversation about how we can help.