What Is Active Sitting? The Idea, the Chairs and the Research

Active sitting is seating designed to make movement easy while you sit: shifting your weight, tilting, rocking, perching, turning sideways or changing position without getting up or unlocking anything. Instead of holding you still in one "correct" posture, an active chair makes the next position easy to reach. The HÅG Capisco is the best-known saddle chair built on the idea, and movement is central to the whole HÅG range.

This guide explains what active sitting is, where the idea comes from, the different kinds of active chair, how HÅG builds it into its chairs, and what researchers have found when they measure people sitting this way.

What is active sitting?

Most office chairs are built to hold you in one well-judged position. Active sitting, also called dynamic sitting, starts from a different question: how do you make it easy for the body to keep changing position through a working day?

The answer is a chair that moves with you. Depending on the design, that might be a seat and backrest that tilt as you shift your weight, a saddle seat that lets you sit higher and perch, or a base that rocks. What they have in common is that moving is the easy option, so it happens naturally, in small adjustments you barely notice, rather than only when you stand up.

It's a design philosophy rather than a single product or a medical treatment. That distinction matters, and we come back to it at the end.

The HÅG philosophy: the next position

HÅG, the Norwegian chair maker now part of the Flokk group, has designed around movement for decades. Its central idea is that there is no single ideal sitting position to hold for a whole day. The Norwegian designer Peter Opsvik, who worked with HÅG from the mid-1970s [1] and designed the Capisco, put it in one line:

The best sitting position is, after a while, always the next one.
— Peter Opsvik (1939–2024) [2]

The thinking is practical rather than mystical. Any posture, however good, becomes less comfortable when you hold it for long enough. So instead of designing a chair that locks you into one position, HÅG designs chairs that make the next position easy to reach, and leave the choice of when to move to you.

Flokk traces the thinking back to 1977, when HÅG invited the Danish physician A.C. Mandal, known for his research on forward-tilting seats, to share his findings. According to Flokk, that collaboration led directly to HÅG's 2000/Docs chair, and Opsvik drew on the same open-hip-angle thinking when he designed the Capisco in 1984 [1].

Why movement and variation matter

The problem active sitting is designed to address is stillness: long stretches in one position, day after day.

Most desk workers will recognise the pattern. The first hour is fine; by mid-afternoon you're perched on the front edge of the seat, leaning on an elbow or shifting every few minutes. Changing position is the body's natural response to staying still for too long, and a chair that makes that easy is working with you rather than against you.

There's also a bigger picture. Large studies link long hours of total daily sedentary time with poorer long-term heart health. In one UK Biobank study, about 89,500 adults wore an activity tracker for a week, and risk of heart failure and cardiovascular death rose more steeply above about 10.6 hours of sedentary time a day, even among people who met exercise guidelines [3]. That is an association in the data rather than proof of cause, and it concerns total sitting time, not the type of chair. An international expert group reached a similar practical conclusion in 2015: desk workers should gradually build up to two hours a day of standing and light activity during working hours, eventually aiming for four, by breaking up seated work with standing work, sit-stand desks and short active breaks [4].

So active sitting is one part of a wider approach to moving more at work, alongside standing, walking and changing tasks. It makes the time you spend sitting less still; it doesn't replace getting up. Our office ergonomics guide covers that bigger picture, including why there is no single perfect posture to hold all day.

What happens when you sit actively

Researchers have measured several things when people sit on active seats: how much they move, the angle of the hips, the shape of the lower back, which muscles are working, and how much energy they use. Most of these studies are small and short, often under an hour in a laboratory, but together they show clearly that seat design changes how you sit.

You move more

In one study, 15 women sat for 30 minutes on each of three seats: a stability ball, an air cushion and a hard seat. Their upper body moved noticeably faster on the less stable surfaces [5]. More movement while seated is the basic promise of active sitting, and in that study, on unstable seats, it held up.

Your hips open up

On a conventional chair, your hips are bent to about 90 degrees. On a saddle seat, your thighs slope down and the angle between your trunk and thighs opens. In a study of 25 people doing a simulated dental task, a saddle stool put the hip angle at about 125 degrees. Compared with a standard stool, the lower back was more arched and the stomach muscles did more of the work [6].

Your lower back changes shape

How you sit has a big effect on the curve of your lower back. A study that X-rayed 30 healthy men standing and in five sitting positions measured these average lower-back curves [7]:

*The paper's results give 47.1° for standing; its summary gives 48.5°. A negative figure means the curve reversed. The study did not include a saddle chair.

The point is how much the seat matters: the same person's lower back changes shape a great deal depending on what they sit on. The authors themselves favoured a chair with back support. A different shape isn't automatically better or worse for your health, which is why we treat this as a picture of what chairs do rather than a scorecard.

Different muscles do the work

On a purpose-built dynamic office chair with a moving seat, ten people's lower back muscles switched on and off in a steady rhythm as the seat moved while they read [8]. The researchers suggested this pattern could be good for the back over long periods of sitting, and called for studies in real offices to test it. One of the authors invented the chair's seat mechanism.

Not every design does the same thing. A study that compared four dynamic office chairs with a conventional one, in the laboratory and in real offices, found that the work people were doing shaped their posture and muscle activity far more than the chair did [9]. On balls and air cushions, the extra muscle activity shows up mainly in the legs rather than the trunk [10].

You use a little more energy

Sitting actively uses a little more energy than sitting still. In one study, a stability ball used 10.4% more energy than a flat, firm seat and an air cushion 9.6% more [10]. In another, an active balance chair raised energy use per minute by 19–40% compared with a standard chair during ten-minute reading and typing tasks, while a stability ball made no measurable difference [11]. Sitting uses little energy to begin with, so these are modest gains in absolute terms. They are real, and they are one more reason active sitting belongs alongside standing and walking rather than instead of them.

The different kinds of active sitting

Active seating isn't one product. It's a spectrum, and the research above shows that different designs behave differently, so it's worth knowing which kind you're looking at.

Dynamic task chairs

These look like ordinary office chairs, with a normal seat and backrest, but have a mechanism that lets the seat and back move as you shift your weight rather than locking you in place. You don't have to change how you sit; the chair simply follows you. This is the most familiar form of active sitting, and the one most people can use all day without thinking about it. HÅG's inBalance chairs, described below, are in this group.

Saddle chairs

A saddle seat lets your thighs slope down, opening the hip angle, and lets you sit higher than a conventional chair: at a normal desk, perched at a raised desk, or astride facing the backrest. Saddle chairs suit people who move between tasks, work over a bench or drawing board, or use a sit-stand desk. The Capisco is the best-known example. Our guide to saddle chair research covers the saddle studies in detail.

Balance stools and unstable seating

Balance stools, wobble seats, stability balls and air cushions have an unstable or tilting base, so your body makes constant small corrections to stay upright. They are what most laboratory studies test, but they aren't what HÅG's philosophy is built on. Staying balanced asks something of the body. A computer-modelling study of 12 people, half of them with low back pain, sitting on a wobble chair in 10-second trials estimated that peak compression at the base of the spine was roughly double that of sitting still, and judged the wobble chair safe for its intended use as a therapeutic exercise [12]. In a one-hour comparison, people also found a stability ball less comfortable than an office chair [13]. Flokk's own advice is that unstable seats work well in short spells, and less well as an all-day replacement for a proper task chair [1].

Sit-stand and perching combinations

Pairing an active chair with a height-adjustable desk gives the widest range of movement: sitting, perching and standing at the same desk over a day. A tall saddle chair covers the height between sitting and standing that most chairs can't reach at all. Our standing desk setup guide covers desk heights and how to split the day.

HÅG inBalance: movement built into the chair

HÅG's own movement mechanism is called HÅG inBalance (sometimes written HÅG in Balance). Flokk describes it as a mechanism that moves with your body, encouraging small, unconscious shifts in posture without asking you to change how you sit [1, 14]. In practice, the seat and backrest move as you shift your weight, so changing position doesn't require unlocking a lever or getting up.

That's the key difference from unstable seating. An inBalance chair is stable: you are supported the whole time, and the movement comes from the chair following you rather than from you keeping your balance. Flokk builds it into conventional-looking task chairs such as the HÅG Tion range, and into the Capisco [15]; the HÅG SoFi Mesh uses what Flokk calls HÅG's centre-tilt mechanism [1]. It's also why the laboratory studies of balls and wobble cushions don't tell you much about an inBalance chair: they are different ways of sitting.

The HÅG Capisco: active sitting in practice

If one chair captures the HÅG philosophy, it's the Capisco. Peter Opsvik designed it in 1984 to offer as many sitting positions as possible, and to make moving between them effortless. Opsvik died on 30 September 2024, aged 85; we wrote about his work in remembering Peter Opsvik.

Sitting backwards on the HÅG Capisco, with the backrest used as a chest support.

One chair, many positions

• Forward. The saddle seat lets your thighs slope down and your pelvis tip forward, so you can sit up close to your work.
• Sideways. The cut-out backrest leaves room for your arms and torso, so you can turn and lean an arm on it.
• Backwards. Sit astride facing the backrest and it becomes a chest support, which suits close work at a bench or screen.
• Leaning back. HÅG inBalance lets the seat and backrest tilt with you as you recline.
• Perching. On the tall gas lift the Capisco reaches perching height at a raised sit-stand desk.

Leaning back on the Capisco. The seat and back tilt with you as you recline.

The specifications

These are Flokk's product specifications for the Capisco 8106, from its current product specification and 2025 factsheet. They describe the chair's design, not clinical evidence.

• HÅG inBalance®. The Capisco also uses HÅG inBalance®, Flokk's balanced tilt mechanism, designed to follow your movement as you shift forward and back. Flokk's specification lists it as a "balanced, flowing tilt function", with adjustable backward tilt tension and a lockable seat [15].
• Three gas lifts. Seat heights of 400–540 mm (150 mm lift), 460–640 mm (200 mm lift) and 550–810 mm (265 mm lift), measured with a load on the seat. The lifts shift the range rather than extend it: the tall lift does not come down to where the standard one starts. Choose by your lower-leg length and desk height rather than your overall height. Full figures for every Capisco and Capisco Puls model are on our Capisco measurements page.
• Seat depth adjustable from 370 to 470 mm; backrest height adjustable from 440 to 500 mm.
• Certified to EN 1335 (2020) Type A and Ax, ANSI/BIFMA, EN 16139 and GS.
• User weight. Flokk publishes no maximum user weight. The 110 kg figure often quoted is a condition of the ten-year warranty, not a load rating, and we don't publish it as one.

For a lighter chair on the same principle, the HÅG Capisco Puls 8010 uses a moulded shell.

Has the Capisco been studied?

Yes, in one controlled study that we know of, and it's a good example of the chair in demanding real-world use. A Mayo Clinic team had four gynaecological surgeons use four chairs in random order across 48 operations averaging about two hours each: a plain round stool, a round stool with a backrest, another saddle chair with a backrest, and a Capisco [16]. The surgeons rated the Capisco and the round stool with a backrest as significantly more comfortable than the other two. Chair type didn't change the surgeons' measured posture or how their body discomfort changed over an operation, and with four surgeons doing one very specific task, the results can't simply be applied to everyone. But in long, demanding work, the Capisco was one of the two chairs the surgeons found most comfortable.

Studies of simple saddle stools, which make up most saddle research, are useful background, but they aren't studies of the Capisco.

Who active sitting suits

A good fit if: you fidget in ordinary chairs, you stiffen up when you hold one position, you change tasks often, you work at a bench or close to your work, or you use a sit-stand desk.

Maybe not if: you want to recline deeply for long periods, you've been advised to use firm, consistent lumbar support, or you find constant small adjustments distracting during precise, sustained work. A conventional task chair from our task chairs range may suit you better, and an inBalance task chair gives you movement in a familiar shape.

For students at a home desk: the Capisco Puls suits a study desk well, but its lowest published seat height is 390–400 mm on the models with a backrest, so measure before assuming it will go low enough for a younger child.

Sitting in one for fifteen minutes will tell you more than any article. Our Sydney showroom is open by appointment.

Setting up an active workstation

1. Pair it with a sit-stand desk. A sit-stand desk lets you move between sitting, perching and standing; check that it goes high enough for the perching height you want. Our sit-stand desk buying guide covers choosing the desk.
2. Add a footring or StepUp if you sit high. At perching height your feet may not reach the floor. The HÅG Footring fits the 200 mm and 265 mm lifts only and is colour-matched to the lift, so specify the two together. HÅG StepUp gives two extra foot levels instead.
3. Put the screen on an arm. Your eye height changes when you change position, so the screen needs to move too. The CBS Flo Single or CBS Flo Dual will do it.

What the research can and can't tell us

The research supports a clear, useful picture of what seat design does. Unstable and balance seats get people moving and use a little more energy; saddle seats open the hip angle and change the shape of the lower back; dynamic chairs change which muscles work in different ways. Different designs do different things, and the work you're doing matters too.

Two claims you'll see elsewhere go further than the evidence. Active sitting hasn't been established as a treatment for, or a way to prevent, back pain: reviews of dynamic sitting and of chairs that open the hip angle haven't found evidence of that effect, and a two-year trial of a moving office seat found no difference in back-related disability [17, 18, 19]. And "core strengthening" claims go beyond the evidence: a review of seven studies found that dynamic sitting didn't meaningfully change trunk muscle activity [20]. More broadly, researchers have not agreed that any particular posture causes back pain [21], so a change in posture isn't the same thing as a health benefit.

That doesn't make active sitting less worthwhile. It means the case for it is the one HÅG has made for decades: a chair should make it easy to keep changing position, because no single position is right for a whole day. If you have a back condition, your physiotherapist or doctor is the right person to advise on seating, and we're happy to work from their advice.

Frequently asked questions

What is active sitting?

Active sitting is seating designed to make movement easy while you sit, so you shift, tilt, perch and change position naturally instead of staying still in one posture. It ranges from task chairs whose seat and back follow your movements, such as HÅG's inBalance chairs, to saddle chairs like the HÅG Capisco and balance stools.

Is active sitting good for lower back pain?

Active sitting hasn't been shown to treat or prevent back pain, so we don't sell it as a treatment. What it does is make changing position easy, and in studies of chairs that open the hip angle, participants often preferred them. If you have a back condition, ask your physiotherapist or doctor what seating they recommend, and bring their advice to us.

Does active sitting strengthen your core?

Not in the way it's sometimes marketed. Studies of dynamic sitting have generally found little change in trunk muscle activity during ordinary sitting, and on balls and cushions the extra effort shows up mainly in the legs. The benefit of active sitting is movement and variety, not a workout.

How long does it take to get used to a saddle chair?

It varies. Flokk's advice is that most people can start using a saddle chair or an active task chair straight away, once it's set up properly, while balance stools are best eased into with shorter spells. A saddle seat does feel different at first, so alternate with standing or your usual chair if you want to, and if anything hurts rather than just feeling unfamiliar, check the seat height or give us a call.

Can I use the HÅG Capisco for a full workday?

Yes. It is a commercial-grade office chair with a height-adjustable backrest and HÅG inBalance tilt, not just a perch. The way to stay comfortable across a long day is to use the range of positions it offers rather than settling into one. Note the warranty condition for long days: Flokk's ten-year HÅG term applies to normal use of up to 9 hours per day, stepping down to 5 years beyond that.

Can I use an active sitting chair with a standard-height desk?

You can, but you won't get the perching positions that make a saddle chair worth having. Saddle chairs work best a little higher than a conventional chair, and a fixed-height desk limits how far you can go. If your desk is fixed, check the seat height range against your desk height before ordering, or call us with the desk height and we will work it out with you.

How is a HÅG chair different from sitting on an exercise ball?

A ball is unstable: you keep yourself upright by balancing, with no backrest, no height adjustment and no castors. A HÅG chair is stable and supportive, and the movement comes from the chair following you. Studies of balls also disagree on how much difference they make, and in one study people found a ball less comfortable than an office chair over an hour. For a working day, we suggest a proper chair.

What is the difference between the HÅG Capisco 8106 and the Capisco Puls?

The 8106 is fully upholstered, with an adjustable seat depth of 370–470 mm and an adjustable backrest height. The Capisco Puls is a lighter moulded chair (the 8010 with a plastic shell, the 8020 with an added upholstered cushion) at a lower price. They are separate chairs with separate factsheets rather than two trims of one chair. Their seat heights differ slightly, and they are certified to different editions of the same standard: the Capisco to EN 1335 (2020) Type A and Ax, and the Puls to EN 1335 Type A (2000). The Puls also meets ISO 14644 Class 4 and 5 for cleanroom use, but only with black antistatic vinyl.

Does the HÅG Capisco have a maximum user weight?

Flokk publishes none. The 110 kg figure in circulation is a condition of the ten-year warranty rather than a tested load rating, and we will not restate it as a capacity. If it is the deciding factor for you, call us and we will put the question to Flokk.

Try it

Active sitting is a simple idea with a long history behind it: the best position is the next one, so a good chair should make the next one easy. The Capisco has been built on that idea for four decades.

Explore the HÅG Capisco and Capisco Puls saddle chairs or the full HÅG range. Chair Dinkum is the exclusive Australian distributor for the Flokk group, of which HÅG is one of eleven brands, and stock is held in Sydney. To sit in one before deciding, contact us and book a showroom visit in Pyrmont.

References

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