Seated ergonomics

It is time to straighten up around here

This is one of those topics in which there are many books and research papers written, and a small blog like this can only scratch the surface and hopefully spark some interest.  Posture, by definition, is the position in which we hold our bodies while performing tasks; in this article I will focus on seated posture, being that the average American sits for 56 hours per week.  Good posture allows our body’s muscles and joints to work more efficiently, requiring less energy, less strain, and helps prevent repetitive stress injuries.

How do we get poor posture?

Well the short answer would be congenital factors and poor habits, often starting from a young age.  Dr. Scott Bautch, of the American Chiropractic Association’s Council on Occupational Health, states that “Emphasis needs to be placed on teaching children how to properly use computer workstations”.  Dr. Bautch went on further to state “Poor work habits and computer workstations that don’t fit a child’s body during the developing years can have harmful physical effects that can last a lifetime”.  A study from Cornell University found that 40% of the elementary school children studied used computer workstations that put the children in postural risk; the other 60% showed “some concern” for postural risk⁴.  Other factors contributing to poor posture can be things like obesity, stress, scoliosis, weak muscles, tight muscles, high heeled shoes, and bad chairs.  Current research is suggesting a correlation of poor posture to the following negative health conditions:  neck pain, shoulder pain, headaches, back pain, difficulty breathing and other respiratory issues, decreased range of motion, decreased functional ability, carpal tunnel syndrome, arm and hand numbness, thoracic outlet syndrome, upper cross syndrome, anterior head carriage, decreased circulation, decreased metabolism, fatigue, cosmetically makes you look older, hyperactive sympathetic nervous system has been correlated to musculoskeletal strain (as a result of poor posture created by a 3/8 inch lift under one foot¹), voice quality, TMJ syndrome, mid back curvature has been correlated to mortality³, psychosocial issues, arthritis, and more. 

I would like to take a little time to focus particularly on what is called upper cross syndrome and anterior head carriage; since this is one of the most common signs as a result of poor seated posture.  Upper cross syndrome is the general idea that chronic poor seated posture will begin to train some of your neck and shoulder muscles to be tight, while it trains others to be weak.  The typical resulting physical appearance, when looking from a side profile, is one in which your head is being held in a position in front of your shoulders, your shoulders are rounded forward, and the middle back has increased curve.  Experts’ suggest that having your head forward one inch, doubles the amount of effort your muscles have to do to hold up your head.  The ideal posture would be to have a side profile of your ears over your shoulders, with your chin tucked in, shoulders in an neutral position, and from the front your eyes, ears, and shoulders should be level, with your nose midline to your body.  This anterior head carriage can be easily observed in the public by simply looking at other drivers; women seem to be more prone to this poor posture while driving, which may be due to women not wanting their hair to touch the vehicles head rest.  Bunch states “For Many years physiologists have shown that the position of the head on the neck is vital because it governs all postural reflexes.  If the head is misaligned, other parts of the body move in and out of line to maintain balance and thus energy is expended to counteract the effects of gravity”².

How do we get good posture?

It takes work, determination, desire, and patience.  Our joints need to have full pain free range of motion. Our muscles need to have appropriate strength and length.  Neck traction is helpful for some people.  Be consciously aware of your posture, check your reflection, have co-workers take a surprise photo of your side profile.  Chiropractors, Physical therapists, massage therapists, ergonomic specialists, and personal trainers seem to be some of the best professions for treatment and advice on how to correct these imbalances.  Remember it has taken you a number of years to get bad posture; it will take years of practice to get good posture. 

Tips for good seated posture

• Computer monitors and Televisions should be right in front of your eyes, not too high or too low, and not to the left or right.  This can be adjusted by physically moving the monitor or adjusting seat height and location of your chair.  Ideally the monitor should be about arms length away from your body, and if you use more than one monitor, the monitor you use the most should be directly in front of you.
• Use an ergonomic low back support.  Some chairs have this built in but if not use a specially designed pillow, or rolled towel.
• The back of your knees should not touch the chair and your feet should be flat on the floor or stool.  Do not cross your legs.  Your knees should be at about hip level.  Your buttock should touch the back of the chair.
• There should be adequate lighting to help prevent eye strain.  For those who use seeing/reading/bifocal glasses avoid tilting your head back to read.  As our eyes get weak during the day, the tendency is for our heads to get closer to the monitor, so try using larger font or have a pair of reading glasses specifically for technology usage.
• While sitting upright with your shoulders relaxed, bend your elbows to 90degrees and that is the height and location your keyboard and mouse should be; be sure to not be reaching out.  Also when using the mouse and keyboard, your wrists need to be in a neutral position; not extended up or angled left or right.  Remove watches or bracelets that limit wrist motion.  Rest your elbows on chair arm rests or on the table top.  Take advantage of new products like gel wrist supports, ergonomic key boards and mouse.  Sometimes it is difficult to adjust keyboard height without an adjustable tray, but you can adjust the chair height to help.
• Micro breaks.  Every 15-20 min stop and stretch your neck, shoulders, forearms, maybe even stand up, then reset your body in to a good posture, then return to your work.
• Additional tips for drivers: your seat should be nearly upright maybe slightly reclined back, use the low back support, the seat should be close enough to the steering wheel that you have a bend in your elbows, use the bottom of the steering wheel whenever possible, rest your head on the head rest to prevent anterior head carriage, do not squeeze the steering wheel, adjust mirrors to a position where they are easily visible without much body movement
• Do not hold the phone to your ear with your shoulder.  Use a headset or your hand and alternate which ear/hand.
• Take the time to adjust your seat prior to driving or working. 

By now some of you are remembering your mother, and/or drill instructor, telling you to straighten up and sit up straight.  The idea of poor posture having a negative effect on our body is nothing new.  Experts report that there is documentation linking all the way back to Hippocrates.  The take home message here is that we all need to make improving our posture a daily goal.  No one is going to be able to do it for you and there are no magic bullet pills.  It has been said that the difference between a wish and a goal is a plan.  So get a book, see a healthcare professional, make a plan and follow through with it. 

Reference:

1. Korr IM. The collected papers of Irvin M. Korr. Colorado Springs,: American Academy of Osteopathey, 1979.
2. Bunch M. Dynamics of the singing voice. New York: Springer Verlag, 1982.
3. Deborah M. Kado MD, MS, Mei-Hua Huang DrPH, Arun S. Karlamangla MD, PhD, Elizabeth Barrett-Connor MD, Gail A. Greendale MD (2004) Hyperkyphotic Posture Predicts Morality in Older Community-Dwelling Men and Women: A Prospective Study Journal of the American Geriatrics Society 52(10), 1662-1667.
4. Healthy Living Fact Sheet: Computer Ergonomics and Children. Journal of the American Chiropractic Association.