By Jane Sleeth
Your employees have no doubt read headlines such as “Sitting is the new smoking" or "Sitting will kill you" or "You should no longer sit at work." But have you stopped to think about what's best for your workforce?
What has been completely ignored and underreported is the very strong evidence (in particular coming from the work at Cornell University’s engineering and ergonomic science program) that static standing postures which occur at sit-to-stand work stations lead to increased biomechanical and physiological loads on the human body, even in healthy individuals. When we stand up statically to work, here is a short list of the changes which occur in the body:
•Increased heart rates. The legs and feet are further from the heart and also being impacted by gravity when standing thus the heart must beat faster to return blood to the heart and lungs.
•Increased cardiac muscle loading during both systole and diastole (beat and rest phases of the heart rhythm). The heart muscle works harder both during its beat and resting phases when standing.
•Increased venous filling in the lower limbs (legs) which in turn can increase risk for DVT (deep vein thrombosis). The veins of the legs become distended and blood flow slows when standing versus walking and sitting.
•Decreased lymphatic drainage from the lower limbs. The veins and the lymphatic system are responsible for returning fluid from the tissues of the body back to the heart
•Increased loading of the joints of the lower body in particular for employees who are heavy or obese.
As you can see, the seemingly innocuous and simple suggestion for a sit-to-stand work station needs to be carefully measured against the significant health risks associated with static standing. Employees should start to take more micro-breaks; perform some tasks in standing such as having impromptu meetings in standing or taking some phone calls in standing; use the stairs at work; and start a regular walking program during lunch hours.
There is a larger body of physiological, biomechanical and mental-function evidence that these more dynamic activities will prevent discomfort and injury from occurring and or worsening and positively impact employee’s cognitive and mental functions at work as well.
Managers and supervisor should be educated on how to provide positive feedback to employees who feel that “If only I had a sit to stand desk then all of my musculoskeletal issues would go away.” There is strong evidence that when an employee hears the same evidence-based message from their manager, ergonomist, physician and rehabilitation team about proper use of ergonomics they are more inclined to change their work health behaviours and report their symptoms.
Sit-to-stand work stations, keyboard trays and other equipment all have an important role to play in an overall ergonomic program in the workplace. However the reasons for their recommendations and the nature of the recommendations needs to be based on solid evidence following careful review of job demands and medical and functional evidence.
Jane Sleeth is the owner and senior consultant with Optimal Performance Consultants, an ergonomic, accessibility and disability prevention firm located in Toronto, which just celebrated its 25th year. Sleeth and her team of consultants can be reached at firstname.lastname@example.org