Athletes who wear red could have a subtle advantage, say Canadian researchers, who have found that the eye perceives red as moving faster than other colours.
Mazyar Fallah, a professor of kinesiology and health science at York University, says wearing red might confer a slight advantage in sports such as figure-skating and gymnastics, where judging is involved.
Fallah points to International Skating Union rules, which include a base score for each element.
"These are based on criteria, which include speed on the ice," Fallah told CBC Radio's Quirks & Quarks. "So, if you're wearing red instead of blue doing exactly the same routine, then [the judges'] eyes move a little faster.
"And maybe that subconscious effect … will actually cause them to bump you up one point more than they would if you were wearing blue."
Fallah said the experiment, conducted with Illia Tchernikov at York's Centre for Vision Research, doesn't show that red skating costumes result in higher scores, only that the eye moves faster when tracking red objects.
"We don't know for certain that this is actually happening … but if it were me, I'd wear red every time," he said.
In the experiment, published this week in the journal PLoS One, five participants took part in thousands of tests where they watched coloured dots moving on a computer screen.
The movements of their eyes where measured using an infrared eye-tracker, a miniature camera mounted on a cap and held near the wearer's nose.
"We found that depending upon the colour of the object, the speed that their eyes moved changed," Fallah said.
Blue at bottom of speed hierarchy
The researchers found that there's a hierarchy of colours when it comes to speed of eye movement, with red at the top, then green, yellow and blue.
"You don't perceive it as being any different in speed," he said. "It's not at the level of consciousness. But at the level of the movement of your eyes, you see these really significant findings between these different colours."
People might not be conscious of the difference in perception, but it exists in the physiology of the eye, he said.
"If your eye is moving faster, it means internally you're perceiving it as moving faster … than if it was blue," Fallah said.
The finding goes beyond sports, of course. The researchers said there could be implications in advertising and designing human-computer interfaces, where capturing a person's attention with colour is important.
As well, the fact this difference is at the level of eye movements suggests that it is evolved rather than learned through a lifetime of looking at stop signs and brake lights.
And wearing red isn't always an advantage, Fallah said. In hockey, it could attract unwanted attention.
"If you're a ref who's giving out penalties … you're going to be drawn to the red players first, and that means you're more likely to see when they commit a penalty than somebody's who's wearing a blue jersey," he said.
Fallah said he'd like to do a study on NHL players to see if they're penalized more in their coloured home sweaters than in their white road sweaters.