Office Ergonomics White Paper - Ki

OFFICE ERGONOMICS

Improved Workplace

Performance and Productivity

Through Movement:

The Emerging Role of Adjustability

Drew Bossen, PT, MBAAtlas Ergonomics

June, 2007

The New Role of Office Ergonomics

EXECUTIVE SUMMARY

Seventy percent of the American workforce sits on the job. This increasingly sedentary work-style often hinders workplace productivity. Problems of poor posture caused by prolonged sitting have further resulted in a variety of health issues, namely degenerative changes to spinal discs.

By contrast, movement is a natural and necessary body function. Regular movement can help maintain productivity and prevent the degenerative spinal problems associated with back pain.

Despite widespread awareness regarding the benefits of appropriate seated posture, health and productivity problems persist. This paper explores the importance of on-the-job movement and the recently discovered benefits of a new breed of office ergonomics promoting furniture adjustability and alternating postures.


INTRODUCTION

Office Ergonomics …exactly what is it? We all have our own concepts, our own philosophies, and our own truths when it comes to the optimal equation of a proper office setup. Yet, over the years, the notion of Office Ergonomics has conjured up a commonly shared mental image. It is of a graphic depicting a perfectly positioned schematic of a faceless individual with each joint of the body precisely measured and labeled. You are familiar with the graphic: a perfectly proportioned individual sitting with knees and hips bent at 90°, an impeccably erect spine, elbows positioned at an exact right angle and finally, the keyboard and the monitor placed without flaw. An ideal picture, or so it would seem. This visual aide has been used countless times by educators and consultants to outline and communicate the ideal position to which end-users should aspire. However, a problem exists. Regardless of how ideal this picture may be, this standard-bearer has seldom, if ever, been observed in the workplace; male / female, east coast / west coast, first floor or the penthouse.

Industry has decided it is time to get practical. The teaching approach and office ergonomics message must match the realities of a call center and / or the rigors of a data-processing suite. People move, shift, reposition and redistribute their weight throughout each day. I do it, you do it, with great frequency and consistency. The paradigm of a statically positioned, faceless individual must transform into a realistic message that strongly encourages worker movement.


MOVEMENT: INHERENT AND INEVITABLE

Since the dawn of time, the human body has been tailored for movement. Whether running from danger or jumping for joy, movement is part of the human experience. Regardless of race, gender, age, size or origin, people choose to vary their posture. We do it to aide the circulatory, nervous and musculo-skeletal systems of our bodies. Plain and simple, we perform better when we move. Hence the notion of that static, fixed posture is misguided and problematic.

THE IMPORTANCE OF MOVEMENT, THE CONSEQUENCES OF INERTIA

Sitting…it sounds simple enough, yet despite years of coaching workers to sit in upright neutral postures, the effects of poor posture persists. Be it a manufacturing engineer, a Ph.D. researcher or entry-level call center trainee, the problem is universal—we continue to observe workers seated with semi-flexed, rounded postures.

This problem has grown alongside an increasingly sedentary workforce. Today, 70% of the American workforce sits on the job.∗ This deskbound work-style has contributed to a variety of related health issues, including the rise in obesity and the increased prevalence of lower back dysfunction.∗ The root of the problem lies in what seems counterintuitive to our daily behavior: the human body is not made to sit for extended periods of time. We are in fact, designed to move.

Consider the definition of the word, movement1:

move·ment ‘muv mənt – Pronunciation [moov-muh nt] – noun1. the act, process, or result of moving.2. the act or an instance of moving; a change in place or position.3. a change of position that does not entail a change of location; [syn: motion]4. (an act of) changing position or going from one point to another5. the act or an instance of moving; a change in place or position.6. the act or process of moving

Movement entails the concept of change, of progression of action, of moving forward versus the stagnant, static notion of traditional Office Ergonomics.


Movement it seems is critical, for at the other end of the spectrum—prolonged sitting—the evidence for non-movement’s damage to the body is overwhelming.Consider the evidence of prolonged seated postures:

The following summary of evidence is the compilation of two researchers and authors, Alf Nachemsom and Robin McKenzie. Nachemson’s primary work focused on intra-discal pressures related to posture. McKenzie’s work focused on the columns of support of the spine and how moving from the posterior to the anterior column affected the inter-vertebral disc.

McKenzie described the spine as having two columns of support. The “Posterior Column” consists of facet joints, a series of interlocking joints that provide a very solid bony column of support. The posterior column reflects an upright neutral standing posture. In essence, the facet column is a “Bony Strut” that runs from the base of the sacrum to the base of the skull.

By contrast, the “Anterior Column” of support is made up of the “Vertebral Body” and the “Inter-vertebral Disc.” The anterior column is less stable and reflects a forward bent posture.

Research confirms that repeated flexion of the spine, particularly in conjunction with increased discal pressures, can weaken the posterior wall of the disc leading to damage of the outermost wall of the disc. This damage typically presents as a “Disc Bulge” or in extreme cases a “Herniated Disc.”

Posterior Column of Support

Anterior Column of Support

Repeated spinal flexion weakens the posterior wall of the inter-vertebral disc. This can lead to a “Disc Bulge” or in extreme cases a “Herniated Disc”.

Posterior Wall of the Inter-vertebral Disc


Upright neutral seated posture. Weight of torso distributed over facet column.

Flexed rounded posture. Weight of torso distributed over the “Anterior Column” of support.

As the weight of the upper torso is repeatedly distributed over the “Anterior Column” of support, the posterior wall of the disc is affected.

PosteriorColumn

AnteriorColumn

McKenzie goes on to describe the effects of sitting. In an upright seated posture, the weight of our upper body is distributed over the “Posterior Column” of support; much like it is in an erect standing posture. With a slouched or rounded flexed posture, the weight of our upper torso is distributed over the “Anterior Column” of support, thus affecting the posterior wall of the disc.

Nachemson’s landmark study in 1976 (A. L. Nachemson, Spine 1, #1, pp. 59-71, 1976) provided new focus relative to the impact of posture as it relates to lower back dysfunction. Nachemson measured spinal intra-discal pressure in various body positions. Lumbar intra-discal pressure was shown to increase in flexed or slouched seated postures and substantially decrease when the spine was positioned in the recumbent position.

Nachemson established that the pressure within the disc is lowest when one lies in recumbent posture. In relative terms, the intra-discal pressure while lying recumbent equals 24 pounds per square inch (p.s.i.). As one moves from a recumbent posture to a standing posture the weight of our body is redistributed. The net result is a rise in the intra-discal pressure; intra-discal pressure in standing equals 100 p.s.i. Nachemson noted an interesting relationship with seated postures; as one moves from an up-right neutral seated posture, a posture in which the normal curve of the spine (the lumbar lordosis) is maintained, to a flexed or slouched seated posture, a rise in intra-discal pressure is noted (100 p.s.i. when seated in an upright neutral posture to upwards of 190 p.s.i. when seated in a flexed or slouched posture).

The pressure (p.si. = pound per square inch) inside the disc changes as we change positions. Pressures while lying vs. standing vs. sitting slouched are noted.


What we learned is that prolonged periods of high intra-discal pressure can cause cumulative tissue breakdown and degenerative changes in the spinal discs; specifically, the posterior wall of the inter-vertebral disc. Advancing degenerative changes due to disc bulge, herniation and/or bony encroachment may cause pressure on spinal nerves. This complicated process is a primary source of degenerative back and neck disorders.

This evidence of degenerative changes to the inter-vertebral disc is supported by NIOSH (National Institute for Occupational Safety and Health) findings that sedentary work (sitting more than half the time at work) is associated with disc herniation for the age group of 35 years of age and older2. Furthermore, “back pain is by far the most prevalent and costly MSD (Musculo-Skeletal Disorder) among industries today.”3

POSTURE: FROM OLD IMPOSSIBILITIES TO NEW RECOMMENDATIONS

One of the UK’s leading ergonomists, Nigel Heaton of Human Applications states, “There is no such thing as the correct sitting position. Sitting in good posture for more than 20 minutes will result in pain simply from the static loading on the muscles holding the weight of the body in position. The human body was designed for movement not stillness. Sitting poorly simply increases the pain levels.”4

According to the writings of Dr. A. C. Mandel, “The erect posture looks very nice, but it is impossible to sit this way for long and there is no scientific basis for it. It is entirely based on wishful thinking, morals and discipline from the days of Queen Victoria. This erect sitting posture cannot be maintained for more than several minutes, and usually results in fatigue, discomfort and poor posture.5 By contrast, current research indicates that the ability to vary working postures throughout the day in a well-designed workplace coupled with tailored breaks and exercise can reduce back and other pains by more than 80%.”6

Winkle and Oxenburgh (1990) outlined the benefits of alternating between sitting and standing postures. Their research determined the benefits of providing active breaks (standing / moving) versus passive rest breaks (sitting) from the point of view of maintaining the health of muscles and the spinal disc. They argued that alternating between sitting and standing positions is the most effective way to maintain productive workflow.7

The posterior wall of the inter-vertebral disc will sustain cumulative degenerative changes when exposed to prolonged periods of high intra-discal pressure associated with flexed or semi-flexed seated postures.


“The ability to dramatically change one’s postures, (from sit to stand to sit) should reduce tension and stress, and improve productivity and efficiency. Sitting all day, every day cannot possibly be as good for us. A variety of postures that include both sitting and standing positions have proven to be advantageous when attempting to minimize the risk of work-related injuries.”8

They further predicted, “The work environments of tomorrow will not be static, or non-moving. Tomorrow’s work areas will incorporate surfaces that will easily adjust up or down to suit the needs of the individual. This will be true whether they are 4’11” tall or 6’6”.”

The workplace of tomorrow has indeed begun to arrive with the ultimate solution for the posture predicament—height-adjustable work surfaces.

THE BENEFITS OF ADjUSTABILITY

Height-adjustable technology allows users to choose from a variety of working positions regardless of their specific body dimensions. Causes of discomfort and injury can be quickly adjusted to fit the needs of the specific user.

What’s more, workers can easily alternate between sitting and standing positions thereby alleviating posture hazards and effectively addressing productivity issues.

The benefits of height-adjustable technology are numerous and include:

Employee Retention, Health and SatisfactionNumerous studies suggest an association between low levels of job satisfaction and upper extremity musculoskeletal symptoms and discomfort.9 “Simply put, when people feel good, they can work as efficiently and productively as possible.”10

In addition, a comfortable and flexible work environment is a value-added benefit for employees leading to improved employee retention. All things being equal, an ergonomically sound working environment can help attract and retain skilled workers.

Quick and Effortless AdjustmentAccording to a Vermont DMV (Division of Motor Vehicle) case study, “The problem with modular furniture is that it is not user-adjustable and most employees do not know it can be adjusted. Once a workstation is loaded with several hundred pounds of equipment, it is virtually unmanageable by a single employee.”11


Electric height-adjustable work surfaces allow a safe and reliable means of adjustment throughout the workday. They essentially eliminate the physical prowess needed with other means of adjustable work surfaces. They lift up to 1,000 pounds with the touch of a button.

Increased ProductivityPeople need to get out of their chairs and move each hour of the workday. Micro-breaks have been shown to increase the body’s blood flow and reduce fatigue. The issue is that many work environments don’t have the flexibility to allow workers to leave their respective workstations each hour. Using sit-stand workstations allow employees to take a break from their static seated postures without leaving their work areas.

Research performed by Miami University of Ohio demonstrated that intermittent standing increased productivity through a reduction in the parameters of employee work breaks. In essence the employees who intermittently changed their postures took fewer and shorter breaks throughout the day. Individuals who did not alter their position (non-standers) took an average of 47% more breaks throughout the day. In addition, the average duration of their work breaks (non-standers) was 56% longer.12

Adaptable: Multi-shift / job Rotation / Internal Churn RateIn many companies, the relocation or internal churn of workers is commonplace. E3 Consulting reports that 40% of the current workforce changes workstations one to three times per year. Even when a company is cognizant of the need for properly fitted workstations, the constant churn of moving people creates obstacles for the deployment of consistent ergonomic initiatives. The solution lies in empowering the end-user to adjust his or her workstation effectively and efficiently. Most workers have a variation of a fixed-height work surface despite the fact that approximately 20% of the workforce reports sharing their workstations with co-workers.13 Electric adjustable work surfaces allow each user to quickly and easily adjust the work surface to meet specific needs related to the task at hand.

The solution must also rely on simplicity. The easier the technology is to use, the greater the likelihood it will in fact be used. Lower-cost, height-adjustable alternatives will likely save initial investment dollars, but in the long run, usage will fragment secondary to the ease of use issue.


Easy Access for IT and MaintenanceWith the ever-changing infrastructure of today’s office environment, technology upgrades are inevitable. The ability to simply raise a workstation to a level which allows ready access to cabling, data ports and power, provides significant savings for IT and maintenance personnel. Many organizations have cost-justified their investments in electric height-adjustable workstations based upon the maintenance savings associated with adjusting slot-wall adjustable work surfaces. Ease of access and cost savings associated with care and maintenance are two important facts to consider.

SUMMARY

The evidence examined overwhelmingly supports the concept that movement or motion is good for our bodies and good for an organization’s efforts to maintain or enhance productivity. Movement is part of the human experience, and it should be encouraged in the workplace. The ability to move must be both accessible and sustainable to ensure desired outcomes. Electric height-adjustable work surfaces are the ideal solution.

move·ment ‘muv mənt – Pronunciation [moov-muh nt] – noun

1. a change of position that does not entail a change of location; [syn: motion]


REFERENCES

1 http://dictionary.reference.com/browse/movement 2 NIOSH 19973 Musculoskeletal Disorders and Workplace Factors – National Institute for

Occupational Safety and Health (NIOSH) 19974 Ergonomics at Work: Important Information About Ergonomics in the Workplace; LINAK 20055 http://www.acmandal.com6 Ergonomics at Work: Important Information About Ergonomics in the Workplace; LINAK 20057 Winkle, J, Oxenburgh, M, ‘Towards optimizing physical activity in VDT/office work’, Sauter, SL,

Dainoff, MJ, (Editors) Promoting Health and Productivity in the Computerized Office, London,

Taylor and Francis, 19908 Stephen A. Marshall; http://ww.ergosci.com/newsletter.html#Page39 Musculoskeletal Disorders and Workplace Factors – National Institute for Occupational Safety

and Health (NIOSH) 199710 Ergo Solutions Magazine, May 200311 Kohn, J.P., The Ergonomic Casebook: Real World Solutions; 199712 Dainoff, M.J., “The Effects of Ergonomic Work Tools on Productivity in Today’s Automated

Workstation Design”, Center of Ergonomic Research, Miami University (Oxford, Ohio).13 Ergonomics at Work: Important Information About Ergonomics in the Workplace; LINAK 2005


This research report furnished to you courtesy of KI.www.ki.comKI-98613/KI/VL/607

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Office Ergonomics White Paper - Ki