Breaking a sweat? Researchers are creating a skin patch that can test those droplets while people exercise and beam results to their smartphones, possibly a new way to track health and fitness.
The experimental gadget goes well beyond activity monitors like the Fitbit. A little larger than a quarter, it’s almost like a tiny lab stuck to the skin — and a study published Wednesday found it worked on sweaty bicyclists, sticking even during a long-distance race in Arizona.
