There's a plethora of devices out there that let athletes, amateur doctors, and even hypochondriacs constantly monitor their heart rates. But thanks to researchers at the Kaiteki Institute in Japan, soon all you may need to keep tabs on your ticker is a cheap pair of in-ear headphones.
Using a technique that measures the subtle pressure changes inside the ear canal caused by the eardrum being vibrated by moving arteries, the researchers were able to accurately measure a subject's heart rate with nothing more than custom software and a cheap $8 pair of earbuds functioning as tiny microphones.
The software can even compensate for ambient noise and earbuds that aren't making a perfect seal in the ear thanks to custom signal processing techniques. And since all that's needed to turn a smartphone into a heart monitor is that custom software, we can probably expect to see this clever technology turned into a cheap app—and hopefully well before the opening ceremonies of the upcoming Tokyo Olympics. [Tech-on!]