What is Dynamic Sitting?

Office chairs fitted with a Synchro mechanism, or synchronous chairs, promote dynamic sitting and improve ergonomic comfort.

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Dynamic sitting occurs in an office chair that is fitted with a mechanism that allows the angle between the backrest and seat to change. By continuously changing this angle, you automatically stimulate, or activate various muscles in your lower back, core and legs. As a result, the blood flow through these muscles increases, bringing oxygen and other nutrients to the muscles and carrying away the waste products of muscle metabolism. By doing so, muscle fatigue and it’s associated pain is reduced, particularly in the lower back, core and legs.

Dynamic Sitting has long been acknowledged as the global benchmark for ergonomic comfort.

Office chairs fitted with either a Synchronous (synchro) or a Free-Float mechanism, encourage or aid Dynamic Sitting.

1. Synchro Mechanism

Synchro mechanisms are mechanical swivel & tilt devices that allow the angle of the chair backrest and seat to change in a fixed ratioA synchro mechanism ensures that the movement of the backrest is always greater than that of the seat.

Most synchro mechanisms have a 2:1 ratio that moves the backrest 2 degrees for every 1 degree of movement in the seat.

dynamic sitting
Synchro mechanisms allow the seat and backrest to move relative to each other in a fixed ratio

Synchro mechanisms promote Dynamic Sitting

The seat and backrest move together in a fixed ratio, where the backrest always moves more than the seat. With a typical 2:1 ratio, the backrest will tilt backwards by 20 for every 10 of seat tilt.

If the mechanism is unlocked, it will be free-floating. In this position, the chair is dynamic and the backrest provides continual back support by moving with you.

Synchro mechanisms are fitted on most of our Ergonomic office chairs.

2. Free-Float Mechanism and Dynamic Sitting

free-float mechanism on orthopedic medical chair promotes dynamic sitting
Orthopedic office chairs have an independent (free-float) mechanism that allows the movement of the seat and backrest to be controlled separately

Free-Float mechanism allows you to independently, or separately, adjust the seat and backrest of the chair. This enables you to adjust the angles of the seat and backrest to suit your preferred sitting posture.

Free-Float mechanisms promote Dynamic Sitting and all orthopedic office chairs use a Free-Float mechanism. What is an orthopedic office chair?

Like a synchro mechanism, if the Free-Float mechanism is unlocked, the chair is dynamic and the backrest provides continual back support as it moves with you.

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