From The Ergoweb® Learning Center

Increased Work Demands Result in Greater Exposure to Ergonomic Risks, But also Increase Productivity

A study of asymptomatic office workers located on the east coast of the United States of America found that those employees who subjectively react greater – physiologically, behaviorally, and cognitively – to normal work demands (high workstyle) are exposed to, or experience more risk factors when performing high stress tasks than office workers performing the same high stress task but who have lower physiological, behavioral, and cognitive response to normal work demands (low workstyle).

In the study, office workers who self reported that they experience greater behavioral, cognitive, and physiological responses (high workstyle) to increased work demands were found to:

  • use higher keyboard force
  • assume greater awkward arm posture
  • express a more negative mood
  • describe greater negative work cognitions
  • have increased work performance during a low stress/high stress experimental task when compared to office workers who described their response to work stress as marginal (low workstyle). 

The study involved 80 asymptomatic computer/keyboard users in a cross sectional investigation that looked at reactivity to simulated job-related demands within a controlled laboratory environment.  The authors defined workstyle as the response pattern of a worker to increased work demands usually involving a multi-factorial adaptation of behavioral, cognitive, and physiological changes.  

The research also disclosed that, when performing the high stress tasks, the high workstyle subjects perceived higher stress and higher work demands than the low workstyle group.  Baseline general stress was higher among the high workstyle subjects compared to the low workstyle subjects.
The Bottom Line – How This Applies To Ergonomists
This study suggests that high workstyle workers become exposed to a series of ergonomic risk factors (force, awkward posture, poorer mood, and negative work cognitions) when a task has higher perceived strain.  The economic tailspin of the last two years has led many businesses and government entities to cut employee positions while increasing work demands on remaining hires.  These conditions may be cultivating a work environment that could lead to a plethora of musculoskeletal symptoms/injury/illnesses among the high workstyle group. Ergonomists should be aware of this, working with employers and employees to understand and improve workstyles and organizational cultures that could lead to uneccessary and preventable MSDs, while still maintaining individual and corporate performance.

Other Key Points
There was no difference in the salivary cortisol, heart rate, or blood pressure between the high workstyle and low workstyle groups during the high stress test.  It was unclear why these objective findings were not consistent with the high/low workstyle group subjective findings.

Sixty-five percent of the study group was composed of minorities.  This may or may not be considered a limitation.  The unexamined norms and attitudes of social groups could have influenced findings.  Also, the application of study conclusions across the country may be questionable.  The authors note this concern but state their study results are consistent with other research.

Validation was done to confirm that the stressful test was actually considered stressful by both the low and high workstyle groups.

Research Method
Via a telephone interview, potential study subjects were assessed relative to inclusion criteria which included:

  • An age of between 18 to 65 years
  • The performance of full-time office work with at least 4 hours per workday performing computer/typing tasks
  • The ability to speak English
  • Eighth grade reading comprehension
  • Scoring in the lower and upper thirds of a workstyle screening tool

The interview also elicited responses involving seven exclusion criteria.

Each accepted volunteer typed two documents – one involving low demand while the second was characterized by high demand.  The low demand task required 10 minutes of typing.  Instructions were given by a relaxed toned voice with no outcome expectations of the task effort.  The high demand task involved typing a document of similar content but the job was explained with instructions spoken in a direct/stern tone.  The task was expected to be completed within a specific time period with errors eliminated through required proofreading/mistake editing.  The subject was told their task success would be determined by their speed and accuracy.

Outcome measurements recorded during both the low demand and high demand task included:

  • Physiological components of salivary cortisol, blood pressure, and heart rate
  • Biomechanical/behavioral measurements of keyboard force, typing task performance, and posture
  • Psychological component  of mood state and task-related cognitions

The study compared the outcome measurements between low and high workstyle subjects.  Also, the physiological, biomechanical, and psychological changes within an individual subject were assessed.

Article Access:
This study can be acquired at:

Article Title: Workstyle in Office Workers: Ergonomic and Psychological Reactivity to Work Demands

Publication: Journal of Occupational and Environmental Medicine, 52:375–382, 2010

Authors: C B Harrington and M Feuerstein

This article was last modified 13 April 2010

This article originally appeared in The Ergonomics Report™ on 2010-04-12.