A Smart Approach to Hydration

A stick-on sweat monitor is changing how athletes stay on top of hydration.

I love my Fitbit fitness tracker. No, I don’t always track my heart rate and I rarely take advantage of the fancy schmancy guided breathing feature, but it does motivate me to maximize my daily steps.

Now, there’s a new wearable in development that ups the self-monitoring game. It's a sweat monitor that will keep track of whether you need to hydrate or replenish electrolytes (hello, Gatorade). According to an article in Popular Science, researchers at the University of Illinois at Urbana-Champaign have created a flexible stick-on patch that attaches to your forearm or lower back and measures electrolytes, glucose levels and rate of sweating.

The article explains the inner workings of the patch: “It sucks up sweat and channels it through tiny capillaries to four circles at the center of the device. Each circle contains enzymes that react to your sweat’s glucose, lactate, chloride and pH levels, each indicating whether you are taxing your body.” The circles change color based on the chemical makeup of your sweat, and an app on your smartphone does an analysis of those colors using the built-in camera.

The patches have been tested on a variety of sports enthusiasts and are being piloted in military training exercises. They are designed to be disposable after a single use and should be able to measure sweat up to six hours a day.

I’m not sure I’m committed enough to put a sweat patch to the test, but it’s a great idea, especially for athletes and fitness enthusiasts in warm climates.