Feeling a little parched after your workout? Check out your seats to know for sure: Nissan’s new technology uses your sweat to gauge your hydration level, The Drive reports.
Design researcher Paulien Routs, in collaboration with Droog Design, has created a prototype for Nissan called JukeSOAK—sweat-sensitive textile coating for the seats and steering wheel of its compact crossover Juke. This colour-changing material responds to the composition of the components in your sweat, which it measures from either your hands or from perspiration on your clothing, according to Routs’s product details.
If the coating is blue, you’re good to go—that means you’re sufficiently hydrated. But if it’s yellow, you’re dehydrated. Colors in between mean you’re not quite hydrated, but not fully dehydrated, either.
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While it might sound cool, it’s more than a fun party trick: Driving while you’re dehydrated could lead to some dangerous results, according to a video demonstrating the technology.
In fact, a 2015 study published in Physiology & Behaviour found that when drivers were mildly dehydrated—the equivalent of losing about 1 percent of your body mass—they made significantly more errors behind the wheel than those who were adequately hydrated. These errors included lane drifting, late breaking, or hitting the rumble strips.
The magnitude of the increase in errors was comparable to that of driving with a blood alcohol concentration (BAC) of about 0.08 percent or driving when sleep deprived, the researchers say.
So it’s possible that this new technology can alert drivers to when they’re at risk due to lapses in hydration—with the hope that they can take measures to correct the issue, like chugging some water, before starting that road trip.
Still, most drivers probably don’t want their car interior randomly changing colours, so the tech may need some slight tweaks before it makes it into production models.
In the meantime, play the preventive game to make sure you’re drinking enough during the day. Your urine can be a clue: Pee that’s straw-colored or lighter likely shows you’re well hydrated, while darker colors that look like apple juice can suggest you’re not drinking enough, hydration expert J. Luke Pryor, Ph.D., C.S.C.S., director of elite athlete performance at Central California Sports Sciences Institute, said.
As for water replenishment after a regular, indoor workout? Drinking to quench your thirst is probably enough, he says—feeling thirsty usually happens when you’re about one to two percent dehydrated.
By Christa Sgobba and Alisa Hrustic; images: Paulien Routs