Afterburners for Runners

Runners will sometimes refer to “hitting the afterburners” at the end of a race drawing on the last reserves of energy to get a final burst of speed.

Well, what about actual afterburners?

Jason Kerestes, an engineering student at Arizona State University, is getting a lot of attention for his 4MM (Four Minute Mile) project, a kind of horizontal jetpack for helping runners move faster. Mounted low on the back, the device uses dual jet nozzles to generate continuous thrust, enhancing the speed of the runner.

In trials this year, the 4MM jetpack showed that it could consistently improve running times over both short and long distances. The device also reduced metabolic expenditure runners burned less energy overall with the device than without it, even though the jetpack adds an additional 11 pounds. The project was initially sponsored in part by the U.S. Department of Defence and DARPA (Defence Advanced Research Projects Agency), in hopes of assisting soldier’s in particular combat situations.

“Our overall goal is really to get any soldier, or any test subject at the time, to be able to run a four-minute mile that wasn’t already capable of doing so,” Kerestes said in the media reports.

Kerestes owns his own welding shop, so was able to create prototypes as he designed. The jetpack uses relatively straightforward technology a lithium battery powers fans that shoot bursts of air through rear-facing nozzles, generating thrust. Tests suggest that the “sweet spot” of thrust power is about 15 percent of a runner's body weight. Less than that doesn’t do much, more than that topples the runner forward.

In the media reports, Kerestes says he’s intrigued by the notion of developing technology that enhances existing human biology. “We’re incredibly engineered as is. Augmenting our abilities really becomes a difficult challenge.”