A wearable exoskeleton might help runners increase their speed by encouraging them to take more steps, allowing them to cover short distances more quickly.

While previous studies have focused on how wearable exoskeletons might help people reduce the energy they expend while running, the brand new study, published today in Science Robotics, examines how wearable robots can assist runners as they sprint.

The exosuit could prove a great tool for athletes seeking to speed up during training. “Although this can be a preliminary study, we will say the exosuit can augment the human ability to run,” says Giuk Lee, an associate professor at Chung-Ang University in Seoul, South Korea, who led the research.

Lee and his team built a light-weight exosuit with steel cables powered by electrical motors attached to the runner’s thighs. The motors pull the cables, mimicking the contraction of muscles. The exosuit helps people run faster by assisting their hip extension—the powerful motion that propels a runner forward.

The exosuit tracks the wearer’s lower-body movements in real time through sensors on each thighs. This data feeds into an algorithm designed to watch gait, which works in tandem with other algorithms to trace each runner’s individual running style and speed.

The team tested the exosuit on nine young male runners, none of whom were considered to be elite athletes. They got three-minute training sessions on how the exosuit works before they ran for brief bursts on a treadmill to familiarize themselves with the way it feels to wear. 

They then sprinted outside in a straight line for 200 meters twice, once wearing the exosuit and once without. They rested for at least half-hour between trials.

On average, the participants managed to run the space 0.97 seconds faster once they were wearing the suit than once they weren’t. 

The researchers observed that the less time it took runners to finish the space, the more steps they took, suggesting that the exosuit helps shorten the sprint time by increasing the frequency of the runner’s steps.

Buoyed by their findings, the researchers have set themselves ambitious goals. They’re working on a customized exosuit for Kyung-soo Oh, a former national elite runner in South Korea who had retired, in a bid to beat the world record for running 100 meters. The present men’s record is 9.58 seconds, set by Jamaican sprinter Usain Bolt in 2009.

The researchers are also beginning to work with a disabled runner to look at whether an assistive exosuit could offer a profit.

“It’s an incredible achievement, what they’ve done,” says Kaspar Althoefer, head of the Center for Advanced Robotics at Queen Mary University of London, who was not involved within the study. He is interested in how the exosuit could help sprinters cover even shorter distances. 

“If they might manage to make a world-record holder run 0.68 seconds faster over 100 meters, I feel it could be massive,” he adds. 

Nonetheless, training wearing such exosuits is unlikely to assist athletes to run more quickly in races where they’re not allowed to don assistive technology. Although the suit encourages wearers to maneuver their legs faster, it doesn’t help their muscles grow stronger, Althoefer says, declaring that over-reliance on exosuits could, in theory, make runners weaker over time.