EMB in the field: Part 1 (of 2)

Today, we have the first part of Ali taking us through a different aspect to what we do here at EMB: fieldwork.

When people ask me what I ‘do’, I don’t tell them ‘Science’, although it would be true. That tends to conjure up images of studious looking people in white coats brandishing conical flasks, test tubes and chemicals over flickering blue Bunsen burners – or perhaps peering at cells, bleary eyed, through the lens of a microscope. That is, of course, science, and it’s important; but it doesn’t represent every facet of the field. Science is varied, and includes a plethora of topic areas – put simply, science is the process of systematically examining the physical and the natural world – a world we, humans, are a part of.

Humans, more specifically how they move, is the focus of my scientific interest. I am a PhD student, and my research is orientated around how humans adapt their walking to cope with variable terrain. What I love about this topic is how relatable it is; it doesn’t matter who you are, what your background is, or what qualifications you have – most people walk, or see others walk, on a daily basis. It’s a process most of us take for granted as we wander around town, negotiating curbs, striding up steps and dodging around crowds of people. But just how do we do it? What allows us to walk around so easily, most of us putting little thought into staying upright, no matter what crosses our path? Why are we one of the only living mammalian species that does all this on two legs, instead of four? How did we come to do it?

These are some of the big questions I think about. Whilst I don’t expect to find the answers to questions on this scale (!), I do hope to break these questions down a little and work out some of the smaller details. The way I do this is by collecting data about how healthy people move. Usually, studies like this are carried out in a gait lab which can look a bit like this one here (The Gait Lab, UoL) – no test tubes and microscopes in here!

a
The Gait Lab at the University of Liverpool, a versatile space where all our various equipment can be set up.

Part (a lot…) of my PhD has involved experiments in this lab but I also wanted to find out about how people walk in natural environments; environments we had to move about in before we manufactured urban towns and cities. This means that I needed to get out of the lab, away from the desks and computers and into the countryside. Let me talk you through a day in the life of this field research.

Located in Liverpool, we’re lucky to be surrounded by a number of fantastic national parks, with miles of open countryside for hill walking, all within easy driving distance; the Lakes, Peaks and Snowdonia are all no more than a few hours away and provided me with some great field days during this phase of my project. However, beautiful valleys, challenging hills and (mostly) wonderful weather weren’t going to be enough; to study human movement I need humans (and a whole lot of paperwork, health and safety meetings, ethical approval and planning, but we’ll skip that here)! Enter volunteers….

b
Nick Thomas, one of our new PhD students, helping out in the field.

Field Day

I had 10 fantastic participants who each gave up a day of their time for the study. In each case, they were fit, healthy volunteers with experience in map reading and navigation (we didn’t want to lose them!). Each field day started with collection of our equipment from the university, and then collection of our volunteer. We (my participant, another EMB researcher, and myself) then spent a few hours cooped up in the car driving to the starting point, sometimes with questionable music choices (I was not responsible for radio control). Once we arrived, the fun and games began.

The Set-up

Now obviously, I need data – this means I needed equipment that collects varying information about how people move during walking. This study involved the following:

  • EMG sensors – these little boxes detect electrical activity of the muscles through the surface of the skin, allowing us to understand which muscles are active when during walking, how long they are active for and so on.
  • Foot switches – these are small membranes which detect pressure. When attached to the boot insole (one at the toe, one at the head of the fifth metatarsal and one at the heel) this allowed me to know what part of the foot was (or wasn’t) in contact with the ground at any one time.
  • A data logger – the EMG and foot switches fed their data to this logger wirelessly, where it was recorded for later use.
  • Heart Rate monitor – a sports watch with Heart Rate capabilities was used. Combined with some exercise data collected on a previous lab visit, this allows me to interpret approximate energy expenditure.
  • GPS tracking – again, using inbuilt capabilities of a sports watch, GPS tracking allowed me to associate all the different data we were collecting, with the location (and therefore the type of ground) at any particular time.

 

All of this just needs taping or strapping onto the body or clothing – simple, right…? Well, sort of. In order to get the best EMG signal we can, we first need to prepare the skin. This involves shaving parts of the leg to remove the hair, and swabbing with alcohol before applying the sensors. It also involves applying sensors quite high on the leg; these requirements frequently resulted in my volunteers stripping down to their underwear at the side of the road whilst we set up (thank you, all of you!), much to the bemusement of the occasional passer-by, who got more of a view than they perhaps had expected when they set off that morning! Once the volunteer was set up (fully clothed once more) and had packed their rucksack with food, water and some safety gear, they set off on their route, map in hand.

 

Join Ali next week as she sets off in the field to collect her data!