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Programmes

Functional Strength Training
in London

Functional strength training builds strength in the movement patterns your body actually uses, carrying, lifting, pushing, pulling, rotating. The result is a body that doesn’t just look strong. It is strong, in every direction that matters.

5.0218 Google reviewsFree 15 minute callNo sales pressure
500+
Body transformations
5.0
218 Google reviews
InBody
770 medical grade scans
1:1
Never shared sessions
7 days
Open 6am to 10pm
BTX coach spotting a client through a barbell back squat in the rack

Functional Strength

What Is Functional Strength Training?

Functional strength training focuses on compound, multi joint movements that train muscles to work together, mimicking real world activities and sport specific demands. Unlike isolation exercises, functional training improves movement quality, joint stability, and neuromuscular coordination alongside raw strength.

Functional Strength

Functional Strength at BTX

01

Functional Training at BTX

Mariyan Voykov brings over a decade of multi sport experience, football, boxing, powerlifting, calisthenics, to his functional training coaching. His programmes are built around athletic movement, not just aesthetics. Clients develop genuine physical capability alongside the physique changes they’re looking for.

02

Who Is Functional Strength Training For?

Functional strength training suits anyone who wants to build a body that performs as well as it looks, whether that’s a recreational athlete, someone returning from injury, a busy professional who wants to feel physically capable in daily life, or a competitor looking to develop sport specific strength.

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Train in North London

BTX is at 529a Finchley Road, NW3. A private studio, fully equipped for functional strength, barbell work, and conditioning, with no queues, no distractions, just focused coaching.

Why BTX?

A gym rents you space.
We deliver a result.

Lasting change needs a programme, not drop in workouts. Everything at BTX is built around your data, your schedule and a coach who is with you for every rep.

A regular gym
  • You rent space and equipment
  • A generic plan, or no plan at all
  • Progress judged by the bathroom scale
  • Restrictive diets you can't stick to
  • Motivation fades by week 3
The BTX method
  • A dedicated coach with you for every 60 minute session
  • Periodised programming built from your scan and movement assessment
  • Body fat, muscle and metabolic rate measured every 4 weeks
  • Nutrition built around your lifestyle, food and schedule
  • Coach led accountability, session after session

How it works

From first call to
first result

01

Book your free strategy call

15 minutes with a BTX coach to talk through your training history, health, goals and schedule. No sales pressure.

02

Get scanned and assessed

Your InBody 770 scan measures body fat, skeletal muscle and metabolic rate, alongside a full movement assessment.

03

Start your 12 week programme

Periodised training and realistic nutrition, with a rescan every 4 weeks, so progress is measured, not guessed.

Client results

Real people.
Measured results.

★★★★★
“I am halfway through my 12 week program and have already dropped 5% in body fat and added muscle.”
Moritz12 week programme · Trustpilot
★★★★★
“I have been training with Justin for over a year and am blown away with the result. Justin and the team really know their science.”
Jean-PhilippeClient for 1+ year · Trustpilot
★★★★★
“The team at BTX supported me in getting my fitness and strength back. Justin is incredibly focused and committed.”
ShivaStrength and fitness · Trustpilot

Free strategy call

Book your
strategy call

  • Pick a time that suits you
  • A coach calls you, with no sales pitch
  • Instant confirmation and reminder
Can't see a time that works?Call 020 8138 9413WhatsApp us

FAQ

Questions,
answered.

Still unsure if BTX is right for you? Ask us directly. We reply fast on WhatsApp.

Training at BTX is priced as a membership, not per session, because lasting results need a programme rather than drop in workouts. We match the plan to your goals on your free strategy call. Most clients train 2 to 4 sessions a week.

Most clients see measurable changes in body composition within 4 to 6 weeks of following their programme consistently. We check it with an InBody 770 rescan every 4 weeks.

No. We don’t prescribe restrictive meal plans. Your nutrition is built around your lifestyle, food preferences and schedule, so it lasts beyond the 12 weeks.

We regularly work with clients managing type 2 diabetes, hypothyroidism, osteoporosis, high blood pressure and recovery after surgery, following NHS physical activity guidance. We liaise with your GP or specialist where appropriate.

Free strategy call

Your 12 weeks
start with
1 call.

Book a free 15 minute strategy call. We’ll map your goals, your schedule and the plan that gets you there.

  • Free, with no obligation
  • Speak to a coach, not a salesperson
  • Limited 1 to 1 slots each month
Book your strategy call

Prefer to talk now? 020 8138 9413 · WhatsApp