Current research reports that increasing activity in your working day improves long term health. Many articles in the media are advising working from a standing position, because of the increase in muscle work. However, standing without the freedom to sit, or at least support the body, is associated with back pain and lower limb pain from the accrual of loads and constant activity in the same muscles (see To stand or sit at work?). For your health, then it is best to intersperse sitting with standing. But if you were to use a conventional chair you would need 2 desks – one to work from in your conventional chair and one to work from while standing. This may not be possible because of space or budget constraints. Instead, you could use a Move Stool (see Working from a stand-up desk) which allows you to sit or perch.
Seat designer Peter Opsvik is well ahead of the field with the design of perches. He designed his innovative Balans Supporter in 1982 (see left). The possibilities for support are many, and the concept quite brilliant. Opsvik takes inspiration for his innovative designs from his close observation of the postures people assume as they go about their daily living. Opsvik observed that when standing for periods of time, people sought support, be it with one knee on a ledge, using the desk to support the pelvis, or resting their back on the wall. From these observations came his series of supports, including a support to enable perching.[i]
Such a simple design for a perch is not new. Indeed, the perch support has been known since 1100 AD. The first extant examples may be found in Exeter Cathedral, dated 1200 AD. These first perch supports were small semi-oval hinged seats attached to the back of choir stalls, where the monks stood to pray. The stalls and their perches were known as Misericord, which when translated means “act of mercy”. Given that these perching seats supported the monks who prayed from 3.00am to 11.00pm, it was an apt name indeed. They were also known as “nodding seats” because the comfort afforded often induced sleep. However, when a monk fell asleep his bodyweight fell forward, the seat collapsed and he slipped off, [ii] no doubt affording light relief to the congregants.
Falling asleep at your desk will not afford your employer amusement. One way of maintaining motivation is to move. The long term health benefits of continual small movements throughout your waking hours are discussed in Working from a Stand-up desk? But as Peter Opsvik points out “we should be alternating between actively using our muscles and relaxing them all the time… the need to alternate between activity and relaxation while we sit is often neglected.”[iii]
In today’s work world where the ergonomic advice is changing from “eliminate muscle activity where you can” to “use muscle activity where you can”, Opsvik’s comment remains very relevant. If you choose to stand to work you can take time out to lessen the load and change your posture by either perching or supporting your upper torso.
Perching is the natural instinct the body has to transfer weight to a seat in order to relax muscles and decrease compressive forces.
While the above balans Supporter was a concept piece, not meant for production, the innovative MOVE stool is available in stores. Widely viewed as one of the most simple yet innovative designs in production, MOVE is the ideal companion to any sit to stand desk. Hydraulic lift adjustment can accommodate sitting and perching in the one device. Moreover, the base of the MOVE is a convex disk that not only encourages movement, but exercises spinal and abdominal muscles in order to maintain balance, thus avoiding unhealthy extended periods of static standing.
The Move Stool avoids the problem that will arise if you use a chair which elevates to accommodate the height of a stand-up desk, but leaves your legs swinging in the breeze. Such a situation creates pressure on the thighs and compresses the blood vessels in the legs, causing swelling and decreasing blood supply.[iv] The MOVE stool avoids such ill effects.
Trunk support is an alternate approach, with the objective being to lighten the load of the trunk rather than restrict trunk posture. In static standing when a support was used for the upper torso, similar to that seen in the picture on the far right, Damecour and colleagues reported a 60 % reduction of activity in the spinal muscles.[v] Muscles in the low back and buttocks are able to relax when weight is transferred to the support. Without the support, spinal loading increases when the trunk is bent forward from the upright position. Even small amounts of forward bending from the upright position without support magnifies loading on the spine because of muscle activity and resultant increased compression in the low back.[vi] The result is PAIN. Standing and resting the pelvis against the desk for support relaxes some of the big thigh muscle but does not relax the back muscles. Using the table as a method of support could be acceptable for very short periods, but not if it means you must bend over your work to access it. Sustained flexed postures, either in sitting or standing, are a surefire way to give yourself a dose of backpain (see Your ergonomic chair may not be the cause of your back pain).
By alternating from supported and unsupported standing, you are alternating between activity and relaxation, and avoiding load and shear stresses on the structures of the spine, and that is essential to short term back health. Providing you are moving when standing, you are also interspersing incidental activity in your day, essential to longterm systemic health (see Working from a stand up desk).
So intersperse your standing with a rest on a perch support like a Move Stool. That way you are looking after both short and long term health.
[i] Opsvik P. (2008). rethinking sitting. Gaidaros Forlag. Oslo.
[ii] Each stall was separated from its neighbor by armrests. Intricate carvings underneath each seat and armrest provide insight into important social events of the time. Remnant G.L. (1969, 1998). Catalogue of Misericords in Great Britain. Oxford University Press, Oxford. Shadwell W. A. Handbook of Medieval Misericords.
[iii] Opsvik P. (2008). rethinking sitting. Gaidaros Forlag. Oslo, p. 36.
[iv] Ebara T et al. (2008). “Effects of adjustable sit-stand VDT workstations on workers’ musculoskeletal discomfort, alertness and performance”. Ind Health, 46(5):497-505.
[v] Damecour, C. et al., (2010). “Comparison of two heights for forward-placed trunk support with standing work.” Appl Ergos, 41(4):536-41.
[vi] Takahashi, I. et al. (2006). “Mechanical load of the lumbar spine during forward bending motion of the trunk e a biomechanical study”. Spine, 31, 18-23