How lifesguards spot someone who’s drowning

Zwemmen

Wild waving and shouting as their head bobs in and out of the water. Is that how to see that someone is drowning? Well, it is in the movies. Sadly, it’s much harder to spot someone drowning in real life. Why’s that? And what can we do about it?

“A swimmer in difficulties is able to attract the attention of bystanders. But someone who is drowning does not call for help”, says researcher Pieter Vansteenkiste from Ghent University (department of Movement and Sport Science). In his research, he takes a close look at the habits of lifeguards: how they scan the area and how quickly they are distracted. After all, it’s of vital importance that there’s no delay in recognising that someone is drowning.

How do you recognise someone who is drowning

People can suddenly be short of breath. Children who end up in shallow water or adults who are suddenly too exhausted. “They splash in the water, but lack the oxygen to shout”, explains Pieter. “We call this active drowning, and they react with what we refer to as an instinctive drowning response.” This phase is only short: if a child drowns, it takes an average of only 20 to 60 seconds before their head goes under.

But there are also those who first become unconscious and then drown. Pieter: “If you don’t know what you’re looking for, you won’t recognise it. They remain motionless and float on the water’s surface, head facing down, and we call this passive drowning.” For example, they may have suffered a heart attack or a stroke, held their breath for too long during a game, or bumped their head on the bottom of the swimming pool when diving in.

Why experienced lifeguards are better at spotting danger

It’s clear that people in trouble in the water are hard to spot. Certainly if you don’t even know what you’re looking for. Experienced lifeguards do know, and they show it in their search behaviour: Pieter Vansteenkiste discovered that they use a different technique when keeping watch in swimming zones. “We measured for how long and in which direction the lifeguards were watching.” To do so, Pieter and his colleagues used an Eye Tracker – a device, fitted inside a pair of glasses, that records the movements of the eyes.

Vital research

Pieter and his colleagues studied seven experienced and nine unexperienced coastguards. “Thanks to the Eye Tracker, we were able to establish exactly where they were looking as they guarded their zone. What did we discover? Although they watched the same areas, the way they did it was different.”

Experienced lifeguards spend more time watching the seas, and most of all: they fix their eyes for longer on zones that can be dangerous. “Less experienced lifeguards look around more fleetingly. Because they are less aware of where to look”, explains Pieter. “Not only that, experienced lifeguards apply a more variable scanning pattern.” This is really important: with a fixed watching pattern there is more chance that you’ll miss an unexpected problem. Pieter: “We call that ‘inattentional blindness’, and the same pattern can be witnessed among children in traffic.”

The research is of vital importance in training the lifeguards, believes Pieter. “It means that you can train the brain to recognise danger. If lifeguards see more pictures of active and passive drowning during their training they can become better at spotting danger.”

“Less experienced lifeguards look around more fleetingly. Because they are less aware of where to look."
Pieter Vansteenkiste
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