Sit Stand & stools

A Partial solution.

The Sit Stand concept  has slowed following work showing less difference in sitting and standing intra-discal pressures than was first thought.  A comeback is occurring as the  importance of keeping staff exercised is recognised.   

The Sit Stand concept is ergonomically superior to the use of existing upright chairs and can be an adjunct to the 2T system which then becomes a 4M concept (and a ‘full’ solution).

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Most people prefer sitting, because it is energy efficient with less action by the Erector Spinae muscles than when standing.   However there are situations where the concept is applicable and as the  importance of keeping staff exercised is increasingly recognised.   The negative consequences of constrained sitting has been described by a number of authorities.  See ☛ Exercise & movement→

Ben SchillerThe first known ‘office-based’ study in the Department of Clinical Sciences and Nutrition, at the University of Chester, Chester, UK, 2016,  compared two days of continuous monitored capillary blood glucose responses to sitting and standing in normally desk-based workers.  The results provided encouraging signs of attenuating post-prandial glycaemic excursion  and why avoiding continuous sitting at work could benefit cardio-metabolic health.  The following articles are referenced:-

  1. Stand mode
    Freed from the constraint of a worktop desk, a stand mode can be easily designed using the 4M concept.  This may help staff to move about and relate to others.
    But, on the other hand prologed standing is tiring and affects venous return and can adversely affect body and cognitive abilities. – Are Standing Desks The Biggest Sham Ever?→    Wilmot EG, Edwardson CL, Achana FA, et al. Sedentary time in adults and the association with diabetes, cardiovascular disease and death: systematic review and meta-analysis. Diabetologia 2012;55:2895–905.Screen Shot 2018-03-09 at 16.35.37
  2. Saunders TJ, Larouche R, Colley RC, et al. Acute sedentary behaviour and markers of cardiometabolic risk: a systematic review of intervention studies. J Nutr Metab 2012;2012:712435.
  3. Gennuso KP, Gangnon RE, Matthews CE, et al. Sedentary behavior, physical activity, and markers of health in older adults. Med Sci Sports Exerc 2013;45:1493–500.
  4. Leon-Munoz LM, Martinez-Gomez D, Balboa-Castillo T, et al. Continued sedentariness, change in sitting time, and mortality in older adults. Med Sci Sports Exerc 2013;45:1501–7.
  5.  Levine JA, Schleusner SJ, Jensen MD. Energy expenditure of nonexercise activity. Am J Clin Nutr 2000;72:1451–4.
  6.  Koepp GA, Manohar CU, McCrady-Spitzer SK, et al. Treadmill desks: a 1-year prospective trial. Obesity 2013;21:705–11.
  7.  Peddie MC, Bone JL, Rehrer NJ, et al. Breaking prolonged sitting reduces postprandial glycemia in healthy, normal-weight adults: a randomized crossover trial. Am J Clin Nutr 2013;98:358–66.
  8.  Pescatello LS, Arena R, Riebe D, et al. (Eds). ACSM’s Guidelines for exercise testing and prescription. Baltimore: Lippincott, Williams and Wilkins, 2013.
  9.  Speck RM, Schmitz KH. Energy expenditure comparison: a pilot study of standing instead of sitting at work for obesity prevention. Prev Med 2011;52:283–4.
  10.  Blaak EE, Antoine JM, Benton D, et al. Impact of postprandial glycaemia on health and prevention of disease. Obesity Rev 2012;13:923–84.
  11.  Service FJ. Glucose variability. Diabetes 2013;62:1398–404.
  12.  Satya Krishna SV, Kota SK, Modi KD. Glycemic variability: clinical implications. Indian J Endocrinol Metab 2013;17:611–19.

Effect of movement on the IV disc

It has been shown that disc nutrition depends on the pumping action of pressure changes due to changes of position and is probably important in avoiding later degenerative changes.  In the context of chair design, movement is comforting and avoids the adverse effects of a prolonged constrained static upright mode on general health (See (Lueder R 2002).  

Effect of axial loading  on sitting

Originally Nachemson and others showed that the standing position had a lower intradiscal pressure than upright sitting.  This suggested that incorporating sitting and standing, with a sit/stand desk, could be beneficial if designed into an office environment.

Screen Shot 2015-09-30 at 15.05.52This concept  has slowed following later work (Wilke 1999) showing less difference in sitting and standing intra-discal pressures and the general recent ergonomic improvement of office chairs.     A number of bio-mechanically efficient stools have been produced which usually incorporate a FTS, contouring and sometimes iliac support.

Screen Shot 2015-09-30 at 15.15.20☜ The Pesko ERGO FLEX M 1_1 also incorporates a ‘wobble”.

A recent, more complex example is the Freedman chair in which the 2 halves of the seat can move independently, intending to accommodate spinal irregularity (scoliosis) and pelvic side tilting.  The emphasis is on the FTS concept and movement.☟

freedman-chair

Screen Shot 2017-02-20 at 18.22.18The HiLo
by Box Clever 2016, an innovation agency led by industrial designers Bret Recor and Seth Murray for Knoll  Knoll produce a number of high end task chairs with semi-remediation such as pelvic support but have not yet made the jump into a fully remediated chair.

It seems to be an indoor version of the old ‘Shooting sticks’ that I used to use.  Very sensible. (→ https://www.knoll.com/search-results?searchtext=HiLo&parent=1347382605724 )

 A ‘stand’ mode can  be incorporated into the 2T concept with a 3M ‘desk-less’ workstation.  This extra mode results in the 4M, the first change since the inception of the concept in 1998.   (See ☛workstations→).

The exact converse system is designed to get the user off the stool to make way for another user.   A good example is an expensive designer stool with 4 legs and painted black as used in Mac shops.  Photo on 06-01-2015 at 12.49Being an enthusiastic  Mac user myself, I am only too familiar with these.  They have a round, horizontal seat without conturing which allows point pressure between the ischial tuberosities (ITs) and the hard surface.

Problems may arise for staff & users who have to sit on them for longer periods. The view is of myself but It can be seen repeated in some random shots of staff users.   In the unavoidable, high loaded, upright position, the pelvis tilts backwards due to  the horizontal surface of the stool seat.  This is augmented by leaning forward, but some slight positive effect may occur by taking weight on the arms.

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A light hearted account of 19c office conditions is relevant here.

Next ☛ A FULL SOLUTION