Most group fitness asks you to keep up. The Tension Method asks you to slow down.
It is the workout we teach at Intension Chelsea: a 50-minute personalised strength session in a group setting, performed on the Tensionformer. It is quiet in a way that surprises people, and it is harder than they expect. This guide explains how it works and why.
The Tension Method at a glance
Length: 50 minutes
Format: group class of up to 14, one Tensionformer each
Principles: progressive overload, time under tension, core connection
Approach: slow resistance strength training, working muscles to failure
Equipment: the Tensionformer, with springs, cables, foot bungee, poles and dumbbells from 5kg to 12.5kg
Focus: strength, not stretch or relaxation
The three principles
Progressive overload
Muscles adapt to the demands placed on them. To keep getting stronger, those demands need to increase over time. In the Tension Method, overload comes from spring changes, longer holds, slower tempos, more challenging positions and, when needed, dumbbells. Your instructor builds the challenge as you build strength.
Time under tension
Instead of fast repetitions driven by momentum, every movement is slow, prolonged and precise. The muscle stays working throughout, out and back, with no point where it can rest. This is where the Method gets its name, and where much of its intensity comes from.
Core connection
Almost every exercise asks you to stay connected through your centre. Whether you are pressing, pulling or holding a plank, a braced, engaged core links the movement together and keeps the work where it belongs.
Working to failure
The Tension Method is built around working muscles to failure: the point at which you cannot complete another controlled movement with good form.
This is where you sweat, shake and burn. It is demanding, and it is meant to be. When the springs alone are not enough to get there, dumbbells from 5kg to 12.5kg are added to increase the difficulty and take each muscle to full failure.
Failure here is not about strain for its own sake. It is a controlled end point, reached with good form, that tells you the muscle has been worked completely. Your instructor will show you how to recognise it and how to approach it with control.
Reaching that point, slowly and under control, is what separates the Tension Method from a workout that simply makes you tired.
Developed alongside the Tensionformer
The Tension Method and the Tensionformer were developed together. The machine was specified by Intension, and the exercises and resistance levels were built around it.
That relationship shows in the details. The spring set was chosen by mapping resistance combinations, giving a wide resistance range, from fine low-end steps to serious load. The carriage and grips were chosen with long, loaded holds in mind. Each choice was made from a teaching point of view, so the Method can be coached precisely.
Personalised, in a group
A group class with personal attention can sound like a contradiction. At Intension, it is the point.
Classes are capped at 14, one person per machine, and the room is laid out so the instructor can see everyone clearly. Within the same class, each member works at their own resistance and progression. A newcomer and a long-standing member can train side by side, each taken to their own limit.
The group brings energy and focus. The instructor brings the personalisation.
What a class feels like
A typical Tension Method class moves through the body in focused blocks, with your instructor guiding spring changes and progressions throughout. The pace is slow, but the effort is high. Your heart rate rises, your muscles fatigue, and by the end of 50 minutes you will have worked hard and with intention.
It is not a stretch class and it is not designed to relax you. You will leave knowing you have trained.
Who the Tension Method is for
The Tension Method suits people who want to get stronger and value precise, well-coached training. It is geared to your strength, fatigue and cardiovascular limits, so it scales from your first class to your hundredth.
If you are new to strength training, light starting resistance and the guidance of your instructor make it approachable. If you are experienced, heavier spring combinations, the added dumbbells and the focus on failure will keep you challenged.
We recommend between 2 and 3 classes per week for maximum results.
Frequently asked questions
How long is a Tension Method class?
Each class lasts 50 minutes.
Is the Tension Method suitable for beginners?
Yes. The workout is personalised within a group setting, and your instructor adjusts resistance and progressions to suit you, so you can progress gradually.
Is the Tension Method the same as Pilates?
No. The Tension Method is a slow resistance strength workout focused on progressive overload, time under tension and working muscles to failure. It is not Pilates, and it is not focused on stretch or relaxation.
What should I bring to my first class?
Bring grip socks (if you have them; if not, they are available in the studio), water and comfortable workout clothes. We have lockers to store your valuables, changing rooms and a vanity area for after class.
Experience the Tension Method
The Tension Method is best understood on the machine, under the eye of an instructor. Reserve your place at Intension Chelsea.