The Captain’s Chair…can you live without arm rests?
There are very few chair bound individuals working with arm rests that would freely give them up to be sitting in the same chair without those reassuring supports at their sides. Very, very few! Despite significant ergonomic evidence recommending against the use of Arm Rests, one thing is clear, we are usually very reluctant to give them up. The exceptions, of course, are those people in pain who are looking for a solution to their discomfort.
So here is a summary of the argument against the use of Arm Rests:
Australian Standard AS 3590.2 – 1990, 7.5 refers specifically to arm rests and states:
Chairs for most keying activities should not have armrests. If provided, armrests should not interfere with acceptable working posture, and should be-
(a) easily detached;
(b) not greater than 210mm in height above compressed seat;
(c) not greater than 200mm in length
(d) set back not less than 110mm from the front edge of the seat; and
(e) not less than 480mm apart, i.e. between inside edges
From a practical ergonomic perspective, arm rests are typically not recommended because:
When too high:
1. They can impede safe working angle of the upper limbs when keying.
2. They can cause pressure points on the forearms and potentially interfere with blood flow to and from the extremities.
3. They prevent free movement of the chair under or around the workstation and therefore compromise postures, typically resulting in sustained trunk flexion (bending at the waist) and rounding of the thoracic spine (C shaped spine).
On top of this, if the arm rests are too low:
4. They encourage lateral flexion (bending) of the trunk to lean to one side which can have gradual onset implications for back alignment and postural decay. Next time you are in a meeting room where the chairs have arm rests, scan the room after 15 minutes to see who is leaning sideways. You’ll have trouble finding anyone sitting straight in their chair.
There are always exceptions to the No Arm Rests rule. Those arm rests can be useful to help transfer some individuals with injuries from a sitting to a standing position. For others, it can be beneficial in orienting them to the chair before they sit down, and therefore be of assistance when transferring from standing to sitting.
In general however, people just seem to like having arm rests because they provide a sense of security and comfort. Maybe it reminds us of our favourite lounge chair or a comfortable couch?
Whatever the case for the use or arm rests on workstation seating, the case against is stronger. So if you are having problems getting comfortable while seated in front of your computer, removing your arm rests may be a great place to start.