Many people believe that sitting without a backrest strengthens back muscles and improves posture. In reality, this is a misconception. In the office, " active sitting " usually means sitting still for eight hours while maintaining good posture – and that's precisely what puts excessive strain on the body.
The spine is designed for movement, not constant tension. Working for hours without back support forces the postural muscles into permanent activity – this doesn't lead to training, but to chronic fatigue .
Why your back needs support
The natural S-shape of the spine only distributes load evenly when it is accompanied by support .
A backrest fulfills three essential functions:
- It stabilizes the pelvis and prevents rounded back.
- It relieves the lumbar muscles so that they remain relaxed even after hours.
- It allows for short rest periods that promote concentration and blood circulation.
Without a backrest, every posture has to be maintained through muscular effort. After 20 minutes, the back slumps slightly, the head tilts forward – a classic pattern for tension and pressure on the intervertebral discs.
What happens in the body when the backrest is missing
I see it regularly in offices: people on stools appear upright at first, but after a short time they slump over.
The consequences are clearly measurable:
- Increased muscle activity in the lower back (≈ +30%)
- Imbalance between the front and back trunk muscles
- Shortened hip flexors, tense neck muscles
- Decreasing concentration after just a few hours
Instead of healthy dynamics, constant tension develops – and this is more harmful in the long run than occasional leaning.
What studies and practice show
Ergonomic research – including research from the Federal Institute for Occupational Safety and Health (BAuA) – confirms: The backrest is not a matter of comfort, but a physiological necessity .
Once the lumbar region is supported, muscle strain decreases significantly, sitting time remains stable, and the risk of back pain is significantly reduced. In practice, teams that switch to chairs with backrests report less pain and improved concentration after just two weeks.
As an example of an ergonomic solution with a supportive backrest, consider the Called the Sihoo Doro C300 Ergonomic Office Chair , it offers an adjustable backrest as well as adaptive lumbar support and illustrates what real support while sitting can look like.
When chairs without backrests still make sense
There are limited situations in which a chair without a backrest is acceptable:
- Short tasks up to 30 minutes
- Jobs involving frequent changes of position
- Targeted training of the postural muscles – short-term
Useful in the short term – a long-term burden. For focused office work, the lack of support is not a functional option, but a compromise at the expense of health.
Warning signs you should take seriously
- Tension in the neck or between the shoulder blades after 15 minutes
- Lower back pain at the end of the day
- Head posture tilts forward (“text neck”)
- Numbness or tingling in the legs
If these symptoms occur, it is not a training stimulus – but a signal that your body requires support .
Conclusion
A good chair doesn't replace movement, but movement also doesn't replace support. Those who sit in an office for extended periods need a backrest that provides stability without restricting movement.
"Exercise is healthy – but only if it is supported."
Without a backrest, the body cannot perform this function. Therefore, as an ergonomics expert, my position is clear: a chair without a backrest does not belong at a desk.
