This is Part 2 of our 3 Part Series all about the ergonomic risks that are associated with long-term laptop use. Haven’t had a chance to read Part 1 yet? You can check it out here. It’s a good place to start as it lays the principles surrounding what is considered an ‘ideal’ ergonomic set-up. This post highlights the ergonomic risks that are specific to just using the laptop for extended periods of time. So, if you use your laptop as your main computing device, you’d definitely want to pay attention to the risks highlighted in this post. Finally in Part 3, we will share solutions that can reduce the ergonomic risk and therefore discomfort and injury.
Ergonomic Risks Associated With Laptop Use
Let’s Start With A Brief Recap Of An Ideal Ergonomic Set-up
In our Post 1 we shared two keys for setting up your workstation. These were:
- The top of the monitor’s screen should be positioned slightly lower than your resting eye height. It should be positioned about one arm’s length away from you. And, the bottom of the monitor should be tilted upwards towards you at approximately a 15 degree angle.
- The keyboard and mouse should be positioned close to you to ensure that you don’t over-extend to use them. They should also be positioned slightly lower than your resting (and comfortable) elbow height.
Compare with a Typical Laptop Set-up:
Let’s move onto a typical or basic laptop set-up. With this, we’re referencing placing the laptop on top of a work surface and getting to work, just like our picture below shows. In this section we are going to be making some comparisons with this typical set-up and the optimal ergonomic set-up that we described above.
1. Laptop Screen Placement
Let’s move onto laptop specific risks. It’s so common to see laptop users looking downwards for extended periods of time, just like our pictures in this section illustrate. Firstly, and probably most obvious is with using a laptop there is a HUGE height difference between the seated eye height and the top of the laptop screen. Remember that there should only be a slight (a few centimetres) difference between the user’s resting eye height and the top of the laptop screen. Too much of a difference can result in way too much neck flexion, which is an ergonomic risk for neck and upper extremity discomfort and injury. Past research on laptop screen placement has indicated that the amount of neck flexion was up to 30 degrees greater than the recommended neutral posture! That’s HUGE!
Moving onto the viewing distance (which is found by extending the arm forward), it is typically MUCH smaller when compared to what is a recommended ergonomic set-up. A shorter viewing distance can compound awkward neck and upper extremity postures. There is usually a reason for this. With a laptop there is a trade-off between the viewing distance and the reaching distance to the keyboard and mouse. With a typical laptop it’s impossible to optimize both the viewing distance and reach distance. And most people will choose to optimize the reach distance to the keyboard and mouse rather than the viewing distance (or screen height for that matter). The good thing is that the screen angle can be adjusted; however this doesn’t make up for poor height and distance positioning.
2. Keyboard & Mouse
When the laptop is placed on the top of a table, the keyboard and mouse are typically much too high for what is considered to be an optimal working position. This can result in a lot of awkwardness in the upper extremities, specifically in the shoulders and elbows, because the body is required to statically hold these awkward postures. Overtime this can become quite straining and uncomfortable. Adding to this point, it’s quite common to see a laptop user lean forward while working. If the keyboard and mouse are positioned higher than the user’s elbow height, there is a tendency for the user to want to lean forward (as mentioned in the above section) to vie for a more comfortable hand working height. This position may give the shoulder relief, but it instead transfers ergonomic risk to the lower back. Leaning forward is one of the most ergonomically risky positions for the lower back. And this can typically result in discomfort overtime.
In a laptop, the keyboard and mouse come as a unit. Although this is a considerable space savings, there is a tendency to have a slightly longer reach to the keyboard compared to a more traditional computer set-up, due to the touchpad mouse positioned in between the user and lettered keys. This can put more strain on the upper extremities, notably the shoulders. Lastly, since the keyboard and mouse use a smaller footprint compared to a desktop set-up, this research found that larger or obese users can be exposed to an increased amount of upper extremity ergonomic risk.
The main ergonomic risks associated with using a laptop for extended periods of time are:
- Excessive and sustained neck flexion (an awkward neck posture) resulting in pain and discomfort overtime; and
- Awkward and static upper extremity postures (including the shoulders and elbows) that can also result in pain and discomfort overtime.
OK, You’ve Found Ergonomic Risk. What Next?
Check out Part 3 here, where we share some tried and tested solutions for prolonged laptop use.
Interested In More Ergonomics? Here are some hand selected articles for you.
- How to reduce ergonomic risk for larger workers
- Product review: Goldtouch keyboard
- The Ultimate Chair Adjustment Guide
- All the wrong equipment in all the wrong places