The Effects of Too Much Sitting
As technology has changed, so have our habits of physical activity with a shift towards more time spent sitting for recreational or work activities. Our computers, televisions and phones exist in front of us so that our posture has gone from being erect to a slumped, flexed posture that puts more strain on all of our joints, muscles, ligaments and intervertebral discs.
In a study by Owen, et al. in the Exercise and Sports Sciences Reviews, researchers found that when one spends most of their time sedentary, it is not simply enough to meet daily physical activity guidelines. Prolonged sitting actually changes metabolic health, so now there is a distinction between too much sitting and too little exercise. The study found that despite meeting a generally recommended 150 minutes/week of “moderate to vigorous” exercise, the subjects who spent more of their time sitting during the day had increased measurements for glucose, waist circumference, cholesterol and systolic blood pressure.
Because of this increase in sitting, we’ve developed new categories for injuries. ICD-10 codes exist for “Dependence on Enabling Machines and Devices” and “Overexertion from Prolonged Static Postures”. When injuries of this nature occur in the workplace, they are called Work-related musculoskeletal disorders or WMSDs and they can affect any of the soft tissue in the body, and are generally attributed to repetitive motions, especially of microtasks. The US Occupational Safety and Health Administration (OSHA) recently estimated that employers are spending “$20 billion per year on worker’s compensation costs related to ergonomic injuries and illnesses.” Awkward and prolonged static postures contribute to risk for injury, especially in the neck, low back, shoulders and forearms.
Current recommendations for work desk set up is that the top of the computer monitor be at eye level and that the computer is perpendicular to the window to minimize glare. The desk chair should have a waterfall edge with hips slightly higher than your knees.
Postural stability (“core strength”) is so important in decreasing our risk for injury and maintaining balance of our opposing muscle groups so that we can stay in our optimal alignment and our muscles are not overstretched or shortened. As we move towards more time spent in static positions, it becomes even more important that everyone participate in some form of movement that focuses on our postural stabilizer muscles.
Owen, et al. Too Much Sitting: The Population-Health Science of Sedentary Behavior. Exerc Sport Sci Rev. 2010 Jul; 38(3): 105–113.
Wynn M. Establishing an ergonomic program. Occupational Health & Safety. 1998;67(8):106-108.