Much of life is shaped by chance meetings. In the mid-80s I was invited to a conference in Switzerland, exploring ‘sitting is a burden’, which means that sitting leads to back pain. Around this time lots of problems concerning our postural system were emerging as more and more people spent longer hours at computers.

The importance of posture was well understood, but there was limited empirical understanding of the underlying complex molecular biological systems. Orthopaedics largely promoted sitting upright and maintaining your spine in good double S curve posture. As physiologists, we had a different perspective to the human body and critiqued this consensus as aesthetic behaviour. For us, the goal couldn’t be static posture. The systems that support the spine need dynamic behaviour; we are made for movement. It was clear we did not have ergonomic furniture solutions for this problem, and that was really the start of the journey we’ve been on for several decades now.

Maria Montisori was clear in her conviction, watch children and you’ll understand what is important for the developmental process of body, mind and soul. She had no research, but she had empathy for what kids do and why they do it.

We began studying the behaviour of children in various settings, and this really challenged our perspective. Why do children rock on chairs so much when learning, particularly forward? Children cannot sit still for more than a minute on average. As we didn’t have any other solutions at that point, we recommended they sit on gym balls. And in no time at all, the gym ball became a sitting ball. These were the first steps and questions that years later led to me working with governments and manufacturers to move beyond traditional rigid modes of sitting.

I first worked with a company from Denmark who designed a static chair with a dish shaped seat, aiding positions for front and back inclination. During development I asked if we could somehow make the chair more fluent/fluid, the user was having to make conscious decisions on which posture to adopt, it was not intuitive enough. He said no! But some years later in the mid 90s the CEO of a German company came to me asking why I’m always against their ideas and what we can do moving forward. From here, step by step we slowly developed a chair with Verner Panton. He was responsible for the design of the shell and frame, and I was responsible for the functional solution, which started as forward and back inclination and later tilted in every direction.

Yes, following the launch of the first iteration we knew the swinging mechanism wasn’t enough, it also depended on the weight and height of the human to get the flexible frame into movement. Over various iterations we developed a new mechanism that incorporated movement in every direction, around 2003 we launched a chair with a 3D mechanism working independent of the height and the weight of the user.

Very much so, I believe Hokki (a flexible stool with multidimensional movement) was launched around the same time. Parallel to all those developmental functionalities in seating we had more research uncovering the strong connection between body and mind, the research was increasingly detailed and consistently demanding activity and movement.

When we first designed the chair with the 3D mechanism, few liked it. A lot of teachers were annoyed all the kids were wriggling, and companies were upset because it wasn’t the classic back support they knew; the company (VS) had strong winds against them. It’s been slow step-by-step progression; people really began understanding the ideas when they were explained as part of a larger concept, not a single solution.

This was first implemented in a project we called Active School, which was initially conducted throughout Hanover from 2000-2014 and ran in parallel with the Exo in 2000. We developed an indoor and outdoor concept that has made exercise an integral part of the learning and living environment in schools. Chairs with movable seats, standing desks, learning on the floor, in the corridors, and on the school grounds were all part of the program, as were teachers who were trained to emphasise student-focused teaching.

We need to serve our bodies as they were designed, to maintain healthy metabolic function that means regular activity. It makes no sense to sit 10 hours a day and then go to the gym or a run for an hour, because the disruption to your metabolic system cannot be compensated with sports in the evening. This is what science shows us today. The body intuitively tells us what it needs; we just have to give it the opportunity to respond appropriately when necessary. In the specific case of sitting, it needs dynamic position changes to avoid biological discomfort.

The results on physical and mental development were not really surprising to anyone who observed the children in this learning environment. But there is also a historical context to this. Anyone familiar with the School of Athens knows that Aristotle’s students, the Peripatetics, used to walk around while learning. We too should hold all our meetings standing up and walking around.

Of course, it was difficult to convince others of the Active School project at the beginning. But currently, around 40% of schools in Germany—mainly elementary schools—are working according to this concept.

Exactly. Active School was just one of many, including Active Office, where we applied the same philosophy to the office environment.

Sometimes there is a contradiction between our mental feeling of comfort and our molecular biological requirements. Comfort is a pleasant feeling, but too much sedentary inactive behaviour is harmful because it often leads to—as is proven through all the research—muscles switching off, joints straining, blood circulation decreasing and posture collapsing. The main issue is that you prevent your body’s healthy metabolic processes, which have a creeping effect that can lead to serious chronic issues. This is why sitting is often described as the ‘new smoking’.

No, and your right, the planar motion of most chairs is not really dynamic enough – but it is still much better than a static chair, of course. The body intuitively performs complex activities to maintain its internal balance. To do this, we need seating solutions that support these necessary changes rather than blocking them. We promoted a similar concept around 30 years ago with the exercise ball, which not only allowed complex pelvic movements but also provided slight bounce, opening up a further dimension of activity in the vertical plane. This is genuine 3D dynamic movement.

The first chair-based solution to implement this concept was the Swopper, manufactured by Aeris and designed by Henner Jahns. It was the first piece of contract furniture to share the same philosophy as a gym ball.

If you put children or teenagers on such sitting solutions, you will see how quickly they get used to it and feel comfortable. If you put adults on it, they will probably feel uncertain at first. Why? Imagine if your eyes are closed for 20 years and suddenly they’re opened, you would be shocked by all the unfamiliar stimuli. Your eyes’ sensory system is no longer used to it. The same thing happens to your body or the sensory system when you sit on a rigid chair for years. It atrophies and loses its sensitivity. So, it is understandable that the body’s sensory system initially reacts with uncertainty when using a three-dimensional seating solution. It takes time, and you have to readjust your body to achieve better physical and mental health.

We now know that your balance system and the sensory system in your muscles, ligaments, joints etc, have a significant impact on the growth of nerve cells and the synaptic switching of nerve cells. It’s why people over 60 are often tested on their balance, improving balance is proven to delays cognitive decline.

The complexity of movement is critical. If you’re under stimulated physically, you’re under stimulated neurally. The more complex, chaotic and natural the activity the better, we have physiological requirements that are not obvious to us. The more muscle activities are revealed, the more your balance system is challenged, and then you’re increasing support for important neurotrophic factors and myoquins proteins which are decisive for the nurse and crows and the synaptic switching of nerves – this is the case at every age. Even at my age, I’m 72, I try to train my proprioceptive system every day by balancing whilst brushing my teeth.

We are currently in the final stages of development. It’s a small device, a motion sensor that’s worn on the hip and based on the same mechanism and philosophy as an accelerometer used in empirical research studies. The sensor is designed to record personal activity levels, especially when sitting. I worked with a tech company called MovX to develop this product for everyday use. It’s similar to a pedometer (step counter), but is designed to give the user direct feedback on their sitting activity via an app. It builds understanding that passive sitting signals unhealthy behaviour, whereas active sitting/movement signals healthy behaviour. The app displays an activity level, a Move Score, with 1.5 being a key threshold. It will be available from 2026.

This 1.5 threshold must be exceeded in order to achieve a healthy metabolic level. These value numbers are based on standardized MET (metabolic equivalent of task) surveys. The value of 1.5 corresponds to walking slowly i.e. a low physical activity level. A value between 0 and 1 basically means absolute inactivity or lazing around. Passively sitting on an office chair has a Move Score between 1 and 1.5. This is still not sufficient for healthy metabolic processes. Above 1.5, as mentioned, means slightly physically active. Between 3 and 6, you are at a moderate level, as with light physical work. A Move Score between 6 and 9 corresponds to athletic activity.

Immediate feedback is crucial: the pedometer rewards you when you check it and see your progress, sharpens your awareness, and can even become a source of motivation. This devise monitors your activity throughout the entire day, which a pedomenter cannot do. Today we sit for about 11 hours a day, so monitors activity over this period is key. As I always emphasize, it is important to spread physical activity throughout the day. This motion sensor helps users visualise the quality of physical activity that occurs even during their sedentary activities.

The body is so smart that, through evolution, we have developed a highly sophisticated biological system. This system is a perfect design that has evolved through our behaviour over thousands and millions of years. Today, we bring this highly developed system, designed for movement, into a completely rigid environment that also offers sensory overload for the eyes and ears. This throws our system out of balance and is extremely harmful in the long term.

I think AI—let’s say the entire digital technology development—is overwhelming us like a tsunami. That’s a huge challenge. Younger generations are growing up with it, and it’s an inevitable part of our future, omnipresent in our daily lives; so we have to live with it somehow. People already sit an average of 11 hours a day. To maintain our health, we must ensure what is anchored in our genetic heritage, such as regular physical activity, is in balance with today’s technological developments. In terms of the need for movement, this means we need to change learning and working environments so that movement becomes an integral part of everyday life. From dynamic sitting and standing desks to flexible work organization processes. And it is high time. We are already seeing an increasing number of people in their forties with metabolic diseases that are traditionally associated with older age. In short, our environment and lifestyle must better integrate the needs of our bodies.

Thank you for the platform and to anyone reading this.