We’ve all see the videos of people walking into fountains, falling off piers, or hitting things while walking and texting. In case you haven’t, here’s an example:

(The woman later sued the mall.)

While these are usually cast as examples of how multitasking is bad, walking while texting turns out to have another embodied dimension: just as using devices while sitting affects our posture, University of Western Sydney neuroscience researcher Siobhan Schabrun recently found that people walk differently when they text. She explains:

For most of us, walking in a straight line at reasonable speed is a simple task. But watch someone texting or reading on their mobile phone and you’d be forgiven for thinking that walking is not as easy as it looks.

People who text and walk (“wexting”) are not only a source of irritation to those of us stuck behind a slow, weaving wexter. Wexting may also put you at risk of injury and… even changes your style of walking.

So how did they do it?

Our study used a 3D movement analysis system to examine how people walk while texting or reading on a mobile phone. We asked 26 healthy individuals (with an average age of 30 years), who used their mobile phone to text on a daily basis, to walk in a straight line in one of the following ways:

  • without their mobile phone
  • while reading a news article on their mobile phone
  • while texting on a mobile phone

Participants used their natural texting style (one or two hands, portrait or landscape orientation, use of autocorrect or not) and eight cameras captured the speed, direction and movement of their bodies when walking under each condition.

We found texting and (to a lesser extent) reading on a mobile phone causes people to walk slower, deviate from a straight path and “lock” their head, trunk and arms together, so they move as a unit (in order to keep the phone steady in front of their eyes).

The effect, she concludes, is

Slow, swerving, robot-style walking that prioritises texting over balance and stability.

Research has shown that people who walk slower, who dual-task, and who walk with a more “locked” (robot-style) posture are at greater risk of collisions or falls.

In addition, people who deviate from a straight path while walking in a pedestrian environment are more likely to wander into traffic or onto train tracks, leaving them at greater risk of serious injury or death.