Chair Series: Armrest Blog

Musculoskeletal disorders result from physical stresses that exceed the ability of the body to withstand them without harm. Such disorders commonly result from the cumulative and sustained nature of exposures over time. It is generally believed that the primary risk factors include static postures, awkward positions, excessive levels of force and pressure or repetition, and quite often a combination of these issues (1). To put that into context, your arms about 8% of your body weight and they play a significant role in distributing the stresses placed on the body, especially the upper limbs.

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Myth Busting: Armrests are just for your arms

As technology has evolved over the years, we are spending more and more time seated at the workstation resulting is us being exposed to potential risk factors for long periods of time. Thankfully, just as technology has evolved, the development of ergonomic equipment to help support us is also evolving. It is no accident that desk chairs have armrests.

Sitting on a chair with adjustable armrest has many benefits in providing support and comfort while they also help reduce upper limb and neck discomfort. Ideally armrests should be 3 Dimensional (3D). Ideally, they should be adjustable in height, width and length. Often armrests are only height adjustable and this may be sufficient. They should adjust enough to allow the shoulders to rest in a neutral position with the arms resting parallel to the desk and in close to the body. We should avoid having to pull the shoulders and arms down and out to reach your armrests. This can often have a counterproductive effect and create tension in the neck and shoulders.

Armrests set at the correct height will allow you to adopt a more neutral position of your shoulder blades, reducing tension in the neck muscles and thus increasing your range of movement. Studies have shown that by supporting the upper limbs results in a significant increase in cervical range of motion. (2) Likewise, it was shown that passively correcting the position of the shoulder blades (supporting them in a neutral position) results in decreased neck pain and improved neck range of movement during active neck rotation in patients with pre-existing neck pain. (3)

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Armrests are good but you still need to Work

The repetitive movements associated with computer work such as typing or using your mouse carried out over long periods can lead to fatigue in the upper body muscles. The affects are not instantly noticeable however, the gradual onset of pain and discomfort come on over a long period of time. Not only are both closely linked but severe local muscle fatigue may be a precursor to long term issues. (4)

In order to reduce the likelihood of muscle fatigue occurring and leading to pain or discomfort you should use the armrests to reduce the pressure your upper body must carry. Setting the armrest to the correct position is crucial and knowing what the perfect position looks like is helpful.

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Make sure armrests are your friend and test their effectiveness

I always encourage people to go a step further and check to see if armrests are actually doing what they are supposed to do, so follow the following steps:

Step 1 - Place your arms on your armrests in their current position

Step 2 - Rotate your neck left and right

Step 3 - Result: If not tension in the neck then they are correct, if there is tension then adjust them up (repeat test), adjust down (repeat) and test until the least amount of tension can be achieved (ideally none).

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Summary Tips

Height – Arms should rest in a neutral position. Armrests that are too high cause you to raise your shoulders, increasing tension in the muscles surrounding the upper back, shoulders and neck. Too low and you will have to slouch or depress the shoulders to reach them.

Width – Around one-inch gap between your sides and armrests. Too narrow and they will impede you while getting into or out of the chair. Too wide and you will have to lean to reach them.

Length – They should be adjustable enough to allow you to sit in close to the desk without the armrests hitting the desk surface.

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Click/Tap For References ↓

1. Blader, S., Barck-Holst, U., Danielsson, S., Ferhm, E., Kalpamaa, M., Leijon, M., Lindh, M. & Markhede G. (1991) Neck and shoulder complaints among sewing-machine operators: a study concerning frequency, symptomatology and dysfunction. Applied Ergonomics. 22(4): 251-257.

2. Andrade, G.T., Azevedo, D.C., De Assis Lorentz, I., Galo Neto, R.S., Sadala Do Pinho, V., Ferraz Gonçalves, R.T., McDonnell, M.K. & Van Dillen, L.R. (2008) Influence of scapular position on cervical rotation range of motion. Journal of Orthopaedic Sports Physical Ther-apy. 38(11):668-73.

3. Ha S.M., Kwon O,Y., Yi C,H., Jeon H,S. & Lee WH. (2011) Effects of passive correction of scapular position on pain, proprioception, and range of motion in neck-pain patients with bilateral scapular downward-rotation syndrome. Manual Therapy. 16(6):585-589. doi: 10.1016/j.math.2011.05.011.

4. Baidya, K. N. & Stevenson, M.G (1988) Local muscle fatigue in repetitive work. Ergonomics. 31 (2): 227-239. https://doi.org/10.1080/00140138808966664.