Wearable sweat sensor shows how hydrated you are during workouts

If genius is 99 per cent perspiration, then that’s a lot of valuable knowledge coming out of our pores. Capturing this is the idea behind a wearable sensor that measures the molecular make-up of your sweat to provide real-time information about your fitness and health.

Sweat contains a wealth of information about your physiology. Wearable sensors have already been used to measure individual components of sweat such as sodium, but this is just the tip of what’s possible, says Ali Javey at the University of California, Berkeley: “If you want to get any meaningful information about your health condition, it’s very important to be able to analyse multiple chemicals at once.”

Javey’s team combined tiny plastic sensors with flexible silicon-based circuits on a band that can be worn around the forehead or wrist. It measures glucose, lactate, potassium and sodium ions, and can transmit the data via Bluetooth wireless technology for more than an hour before it needs recharging. The ions reveal how hydrated you are, and lactate is a sign of muscle fatigue.

Not just a handy gadget
Because the sensors can be altered to measure other chemicals, Javey envisages it as being more than a gadget for fitness fanatics. “We’re trying to use these for clinical studies, for patients, for elderly people, and for people with depression,” he says.

The device could measure the stress hormone cortisol or proteins with concentrations that tell us about the mental state of people with depression, for example. “The device could be a way to remind an individual that maybe they should take a pill,” Javey adds.

“What’s important is that they have produced a fully functional system that is fit for purpose,” says Dermot Diamond at Dublin City University in Ireland. More trials will be needed to determine that the sensor is only picking up what comes from the skin rather than being contaminated by external sources, he says.

Source: newscientist.com