Rachel Bachman wrote for the Wall Street Journal that some of the best ways to make cyclists more visible to drivers are also the simplest, new research says.Highlighting the motion of pedaling can make cyclists more conspicuous, according to two recent experiments. Rick Tyrrell, a psychology professor at Clemson University, plans to submit his findings to academic journals this summer.

In one experiment, Dr. Tyrrell put 186 college students in a car—“not all at the same time, obviously.” One by one, the passengers were driven along a 15-minute route and told to press a button each time they were confident that they saw a cyclist.

A stationary cyclist was placed along the route facing away from the car. The cyclist wore one of four combinations of clothes, from all-black to nearly all-fluorescent yellow.

Although fluorescent jackets can make people more visible generally, in this experiment the fluorescent jersey didn’t make the cyclist significantly more recognizable as a cyclist than a black jersey. When the cyclist wore fluorescent leg coverings, however, observers recognized he was a cyclist more than three times farther away on average than when he wore black leggings and a fluorescent jersey.

“Humans are really good at recognizing other humans,” Dr. Tyrrell says, noting that pedaling a bike is an obviously human motion.

Cyclists and pedestrians tend to overestimate how visible they are to others, previous research has shown.

In Dr. Tyrrell’s other experiment, he and his students tested the use of taillights to increase cyclists’ visibility during the day. Both studies were funded in part by bike maker Trek Bicycle. While nighttime cycling crashes are more likely to be fatal, about 80% of crashes occur during the day, when most cycling takes place, according to U.K. data.

The Clemson experiment found that from a distance of 200 meters, or about one long city block, a flashing taillight is significantly more conspicuous than an always-on taillight, which in turn is significantly more conspicuous than a taillight turned off.

But most eye-catching of all: a solid light worn on the back of each ankle. The researchers custom-rigged taillights with ankle straps for the experiment. Trek’s parts-and-accessories brand, Bontrager, doesn’t make ankle lights.