THE FUSE

At first glance, the newest device from PNOĒ looks like something a comic-book villain might wear. The mask, which covers the nose and mouth and straps around the back of the head, bears more than a passing resemblance to the one worn by Bane, Batman’s hulking nemesis. But its purpose is far more benign; it measures how much oxygen you consume and how much carbon dioxide you exhale, then turns that data into advice about how to eat, train, and, the company hopes, live longer.