During this year around 30 million people in the UK will experience back or neck pain. There are many causes of these debilitating conditions including sedentary lifestyles and spending hours working at a desk, often aggravated by poorly designed chairs.
Dr Brian Hammond, Chair of BackCare, said: “One solution for back and neck pain sufferers is to use chairs that provide support for the spine to minimise strain. BackCare is keen to promote and endorse furniture companies that design and manufacture chairs that adapt to body movements and support various body shapes and sizes.
“The charity is delighted to endorse a number of chair manufacturers producing ergonomically designed chairs which help improve the seated posture. So much time is lost through people suffering back pain and products that help to decrease pain and improve quality of life are to be welcomed.”
Mike Brewster, Status Seating’s sales director, said: “People often suffer from back pain after sitting in offices for long periods on unsuitable chairs. Our chairs are designed to optimise people’s postures and health and well-being. BackCare’s endorsement is clear evidence of the importance of the design and manufacture of furniture that supports the spine”.
Status Seating will be exhibiting their chairs and other products at The Back Pain Show, organised on behalf of BackCare at St Andrews Stadium, Birmingham, on Friday & Saturday 19 & 20 May. Entry to the show is free by registering at www.thebackpainshow.co.uk where details of all exhibitors and the free-to-attend programme of speakers and presentations can be found.
BackCare is the leading UK charity for people and organisations affected by back pain, as well as professionals involved with treating back pain sufferers. It aims to significantly reduce the burden of back and neck pain by providing advice, guidance and information on preventing and managing back pain. www.backcare.org.uk
There are now several scanning techniques employed to create 3-Dimensional imaging or Whole Body Surface Anthropometry. However, the TC2 body scanners used by “Size USA” or the white light BVI scanners used at the University of Aston in association with Select Research will eventually result in a bank of real statistical data that will be representative of all types of individuals dependent on body shape– not an inferred statistical assumption. The data is being collected to provide indicators of potential illness or disease and is used extensively by the UK National Obesity Centre at Heartlands Hospital in Birmingham, but is equally useful in considering furniture design or selection.
These new techniques are measuring the body including the soft tissues – an existing science known as Somatometry – and creating a new set of predictable natural laws for understanding body shape – Somatonomics. International research will continue for some years yet, but for now there are just tantalising glimpses of what the ergonomic seating sales foot-soldiers and ergonomic assessors have known for many years:
- Individuals do not always have classical (average) body proportions.
- In general the action of sitting for women is different from men due to physiology.
- Body Volume displacement is different between gender, ethnicity and occupation.
- As we reach middle age our body shape changes due to spinal degeneration and Body Volume distribution.
These issues do not change the need for all individuals to require a comfortable back support when sitting, or that movement is always better for the body than long periods of sitting, but it creates a challenge for designers to identify the specific needs of an individual rather than fitting the individual into a chair designed for the average user.
In a world where individuals are working for longer, sitting for longer, and subjecting our bodies and minds to increasing stress it is ever more important to find the right work chair for the individual.
The science of understanding an individual’s personal body shape and how it can affect the interaction in his or her personal working environment is upon us. It is more than Ergonomics. It is Ergosomatonomics.
It might only be a few years before employers are placing orders for an ergosomatonomic chair to suit an individual subject of pre-determined BVI Body Type F14T-PAC, (or some other such categorisation), that may mean nothing to us today, but will define a person’s gender-specific body shape, life expectancy, insurance category and credit risk.
It is estimated that during the course of an average office worker’s career he or she will have sat in more than 3 but less than 15 different types of office chairs. Statistics don’t actually tell you much really. Some workers stay in the same job for many years and develop a personal attachment to their office chair. Others move between jobs.
Over decades office chair design has been driven by the need to comply with adjustable functionality based on Anthropometric guidelines. These averaged body and limb measurements obtained from small samples of evenly-gendered subjects from the UK (or more recently from sample data collected around Europe, or in some studies aggregated from data sourced from around the World) set the limitations on component and product design. We are supposed to accept that statisticians can predict a standard deviation around the mean average of a small sample population and that the guidelines will suit 90% of office workers. That is the basis on which the minimum standards are calculated.
Even in the USA, the hotbed of much of the 3-Dimensional anthropometric modelling research that has driven ergonomic seating design into the 21st Century, seating adjustability has been calculated on a sample of only 4431 individuals compiled from studies across the US and Europe. The resulting industry norms, through the application of inferential statistics, have led to the creation of products purporting to suit the mass market – the 5th to 95th percentiles of an inferred normal distribution.
However, at the sharp end, when you are up close and personal with the individual user, things can often look and feel very differently.
The vast majority of office chairs, designed specifically to fit the guidelines, allow for only the standard deviation of adjustability. In reality there are many individuals that are not average. The effect of only matching standard international guidelines for chair design is that the specific needs of individuals are obfuscated during the average measurement process.
The challenges of allowing for adjustability for a user’s height, for longer or shorter limbs, may have been taken into account when designing the chair, but what about body mass, body volume, or the natural laws of gender, ethnicity, age, proportion or well-being?
What about the personal stature, shape or combination of shapes that makes the human being the individual? What about the physical displacement of the person’s body volume? This deeply affects our personal interface with the office chair, has no statistical link with body height or limb length and can adversely affect our sense of comfort or support whilst sitting.
If you have ever been out at the coalface talking to people about their personal chair nightmare you will know that every individual has a different story, a different sub-set of problems, a different body shape; a different solution from the average.
For many years seating companies and DSE assessment companies have focussed on the limb measurements of individuals in order to influence or suggest the selection of a particular combination of seat pad size, backrest heights or armrest adjustment levels. Indeed, this practice has resulted in the creation of indicative average (anthropometric) measurements in order to determine the “correct” sizes for the purposes of the creation of norms.
However, limb measurements are implicitly 2-dimensional – point A to point B – without a true relation to other more 3-dimensional characteristics. This is particularly true when assessors try to measure individuals with unusual body proportions caused by the distribution of their body volume.
Implicit in the process of limb length measurement is the need for the user to be seated. This brings new and unexpected implications to any recorded measurements. This is particularly the case for individuals who possess a higher level of body volume at the rear, large thighs or large calves. We can refer to this as a user with “Excess Lower Body Volume”- ELBV.
Users with ELBV often demonstrate a longer popliteal (buttock to inside knee) length due to the additional body layers at the rear. This body volume distribution can also result in heightening the position of the body on the chair so that the position of the lumbar is also raised. There is also a possibility that the popliteal length is reduced because of the body volume at the rear of the calf that corresponds with the position of the front of the seat pad.
The purpose of these examples is simply to illustrate that it is often an understanding of the 3-dimensional interaction of a user’s Body Shape that influences the correct size or “fit” of chair for the individual, rather than a simpler assessment based on 2-dimensional measurement.
In 2013, Status adjusted its Anthropometrical Data Sheet to include an indication of body shape, also adjusting its assessment sheet to be known as a Body Shape Assessment Form.
Limb measurements are important, but having a more representative indication of a person’s shape helps employers to find a chair that is more likely to be a “fit” for the individual.