Ergonomics That Actually Matter for Your Back

Last week, we covered movement skills and tips. This week, I want to focus on where most of us spend the majority of our waking hours - at work! Whether you sit at a desk, stand on your feet, or some combination of both, there are a few straightforward things you can do to reduce the strain on your back.

Overarching concept

Ergonomics always comes down to manipulating 3 main factors:

• Force
• Posture
• Repetition

To keep us below our injury thresholds and improve work experiences for everyone. We want to be mindful of these factors when considering how to protect our backs. However, real life isn't a calculation, so we'll focus on some more practical tips.

"No posture is perfect. There are only postures that you've been in for too long."

If you work a desk job

Should you get an adjustable ergonomic desk chair with lumbar support and armrests? Yes. An ideal chair and desk setup has these features [1]:

Chair:

• Seat height adjusted so knees are at approximately 90° with feet flat on the floor or footrest
• Seat pan depth allows about 3 fingers of space between the back of your knee and the seat edge
• Armrests supporting the elbows in line with the shoulders — not too high (shrugging) or too low (unsupported)
• Backrest providing lumbar support

Monitor:

• Screen at arm's length and directly in front of you (not off to the side)
• Top of the monitor at or just below eye level

Keyboard and Mouse:

• Keyboard close enough that your elbows stay near your body
  • Wrists straight, not extended upward

Desk:

• Appropriate height to align with your chair (which is usually adjustable)
  • Arms should rest at around 90 degrees
  • Adjust screen and monitor heights with risers

Does that solve all of the problems? No. In the 'how injuries happen and tissue mechanics' section, I outline how remaining in a given posture for extended periods of time can increase our susceptibility to injury. The same is true when you're sitting. The ergonomic chair can support you in much better positions than slouching, but there's another layer.

Movement breaks are just as, if not more important than, your ergonomic setup [1]. In a perfect world, we would all do both. So what should you do?

1. Sort out your ergonomics as best you can right now by adjusting your current setup.
2. Get a timer and set it for 30-40 mins.
   • Timers include: your phone, kitchen timers on your desk, or my personal favourite - an app on your work device. 'Flow' is my app of choice because you set the timer intervals, and you can set it so that a full-screen pop-up appears when the time is up, so it is impossible to miss. Search "flow timer" to get the app for free. I'm sure there are many others as well.
3. Stand up and move a little each time your interval is over. Repeat.
4. Look into cost-effective ways to improve the ergonomics of your setup. Ask your employer if there are any other chairs, desks, risers, or footrests available in the office. The solution might be easily accessible now that you know what to look for.
5. Consider purchasing your own upgrades if possible

A comment on a trend of sit-stand desks. Many people think that they should replace sitting with standing at their desks. This is not recommended. A clinical protocol developed to elicit back pain is simply standing (relatively still) for 2 hours [2]. If you have access to a sit-stand desk, great! Use it to switch between sitting and standing every 30-60 minutes.

If you're on your feet all day

On the flip side, if you work a job that requires you to be standing the whole day, you have a different problem - particularly if you can't move around much but must remain standing. Sustained spinal compression and muscular fatigue increase injury risk while pain creeps in from extended loading.

Here are a few things that can help:

• Shift your feet often and think "soft knees."
  • Shifting your weight around provides loading variety to your spinal joints
• Raise and rest one foot at a time on a low surface
  • This reduces the development of pain in people with low back pain [3]
• Anti-fatigue mats (if applicable to your workplace)
• Take sitting breaks when you can
  • Again, interrupt the sustained posture and give your tissues and joints a chance to reset

Sidebar: Neck and upper back tips

Some quick tips worth considering are:

• Bring screens to eye-level when possible
  • Hold the phone higher
  • Put computer screens on risers to bring them up to eye level
• Avoid a forward head position. Forward postures increase load on the cervical spine and are linked to neck pain [4].
  • Catch yourself when you're slouching and perform chin tucks to train weakened neck flexors
    • Exercise described in the exercise library

The common thread here is variety. No posture is meant to be held forever. Set a timer, change positions, and give your tissues a chance to reset often. As always, have a great weekend.

Best,

Mitch

References

[1] Sonne et al. (2011) — https://doi.org/10.1016/j.apergo.2011.03.008

[2] Nelson-Wong & Callaghan (2010) — https://doi.org/10.1080/00140139.2010.500400

[3] Fewster et al. (2019) — https://doi.org/10.1016/j.humov.2019.03.013

[4] Douglas & Gallagher (2018) — https://doi.org/10.1016/j.apergo.2018.02.020