You probably sit at a desk chair, nearly motionless except for your hands, for eight hours a day. Do you think that's healthy? It's obviously better to move around and burn calories throughout the day.
That, anyway, is the basic idea behind the growing trend of active seating. The solutions range from intentionally uncomfortable stools to inconvenient furniture and exercise balls. Office chairs are the enemy. And that's why Wilkhahn has just produced the On, a chair designed less for making you comfortable, than accommodating a range of sitting positions, so you can fidget as much as you want:
Designed by Wiege, the On was five years in the making, and the research effort involved everyone from kinesiologists to materials scientists. The main insight was that the right chair isn't right for everyone--you might spend years designing the most ideally comfortable chair, only to find that for some, it ends up causes long-term pain. The On, by contrast, has a several "joints" that allow the eat pan to tilt forward, back, and side-to-side--so your seating position can change constantly.