Wearable gauges fitness through stress hormones in your sweat
 

Cortisol (best known as the stress hormone) is handy for tracking your athletic performance and even spotting signs of disease, since it reflects how well your adrenal or pituitary glands are working. But there's a problem: measuring that often take...

https://www.engadget.com/2018/07/20/...in-your-sweat/