Science
Tom Buurke walks on the split-belt treadmill. It has two belts that run at different speeds.

Tom Buurke’s fascination with balance

Walking is actually falling

For many people, walking is as easy as breathing. But movement scientist Tom Buurke doesn’t think it’s all that obvious. He studies the importance of balance in learning to walk.

Thijs Fens

Door Thijs Fens

14 January om 12:58 uur.
Laatst gewijzigd op 14 January 2020
om 16:54 uur.
Thijs Fens

By Thijs Fens

January 14 at 12:58 PM.
Last modified on January 14, 2020
at 16:54 PM.

You’re criss-crossing the Vismarkt, walking over the uneven pavement stones, avoiding others as you keep half an eye trained on your cell phone. You turn left and right effortlessly. You take a step, lean forward, and then take another step to prevent yourself from tumbling over. Walking is actually like falling, but with every step you take, you find your balance, all without a thought. 

‘We don’t realise how good we are at it until we run into issues controlling our balance’, says Tom Buurke. ‘Take older people who have trouble walking, or someone suffering an ankle injury.’

Over the past three years, the twenty-six-year-old movement sciences PhD student has studied approximately 120 people to figure out how they walk. To do so, he had them walk on what’s called a split-belt treadmill. ‘Essentially, it’s two treadmills next to each other, with one of them running faster than the other’, Buurke explains. ‘It basically teaches people a new gait.’ In other words, a new way of walking.

Longer effect

The test subjects were divided into two groups: one group was allowed to hold the railing next to the treadmill, while the other was not. It turned out that the people in the group with the railing very quickly figured out their new gait. The other group had a harder time learning it, but did improve over time. 

The people who weren’t allowed to hold on to the railing had learned much more

‘We drew our real conclusions from the after-effects’, says Buurke. When the two treadmills were switched back to the same speed, the people using the railing quickly managed to switch back to their regular gait. ‘That indicates that nothing actually changed in their way of walking.’ In the test subjects who hadn’t been allowed to use the railing, the effects of the changed gait lingered for much longer. When they were switched back to normal speed, they again had trouble walking. ‘That means that something had actually changed in them. They had learned much more than the other group.’

Cerebral haemorrhage

For his thesis, Buurke moved to Los Angeles for three months to join ongoing research performed by neuroscientist James Finley. He studied 21 test subjects who had suffered a cerebral haemorrhage. 

Studying this group was much more labour-intensive; he easily spent ‘four to five hours with each subject’. He had to perform extra tests on them that he hadn’t had to perform on the healthy test subjects, and the subjects in LA needed a break more often. The study took a lot out of them, but they were all more than happy to participate. ‘It allowed them to do something for other people who might suffer the same fate.’

I’m really interested in the problems people face when they can no longer walk

Cerebral haemorrhages often leave one side of the body affected. ‘If you mess up someone’s gait on the split-belt treadmill and people have to use their weaker leg to prevent themselves from falling, it affects their sideways balance’, Buurke explains. This means that instead of falling forward, they fall to the side. ‘That didn’t happen when they had to use their healthy leg.’

Buurke says the study shows just how important balance is in learning to walk. This is valuable applicable knowledge. ‘A patient being taught how to walk should not be using a railing or other means of support, as it means they’ll learn faster, like the test subjects who didn’t use the railing.’

Unique gait

When Buurke started studying movement sciences in 2011, his focus was mainly on athletics. ‘I’m still really interested in that’, he says. ‘But at one point I became fascinated by walking. I’m really interested in how easily we walk, and the problems people face when they can no longer do so.’  

Outside, he immediately picks out people who have a unique gait. ‘I guess I just have an eye for it now.’ Everyone has their own specific way of walking, says Buurke, and sometimes he recognises people just from their gait. ‘I can even hear it sometimes. Someone will be walking through the hall and I quickly know who it is.’

Buurke wants to continue in the field of science and is looking for a post-doc position. But first he has to defend his thesis, on January 20. James Finley will be flying over from Los Angeles to attend. ‘I’m beginning to get a little nervous’, says Buurke. ‘It’s going to be a special day no matter what, and I’m really looking forward to it. It’s a great way to close out this time in my life.’

Translation by Sarah van Steenderen

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