FitBit's turn in the wearable fitness tech spotlight may be over, with US researchers developing a new wearable sensor that instead monitors a user's sweat.
Wearable sensors currently available, such as the wristband FitBit, measure a wearer's activity levels based on their heart rate.
But the new sensor developed by a team at University of California, Berkley instead analyses an individual's sweat, which is rich in information about a person's health and physiology, in real-time.
Due to sweat's complexity, the array of sensors focuses on collecting measurements of electrolytes in the sweat -- potassium and sodium ions -- and metabolites in sweat -- glucose and lactate.
It also monitors the temperature of the skin in order to calibrate the sensors.
The information is then wirelessly shared in real-time to their custom-developed mobile app, which tracks both the data and trends.
In the research paper published in the Nature journal today, the team says placing the thin device in different locations -- such as the wrist or the forehead -- can show the variations in electrolyte and metabolite concentrations in specific sites.
Professor of Electrical Engineering and Computer Science Ali Javey at Berkley says the goal of the project was to get "accurate and meaningful information about the physiological state of the individual".
"Sweat provides us with a wealth of information about the body condition; it consists of a wide spectrum of different chemicals."
It's hoped that the gear could be used not just by fitness-nuts, but that it could be used in the medical field in the future.
"A medical technician could get a reading on somebody instantaneously and then follow that, instead of taking a blood sample and sending it to a laboratory, and waiting several hours for a result," says Professor of Integrative Biology George Brooks.
"It's the beginning of a great new realm in bio-sensing."
The flexible sensors can be tucked under a sweatband or as a wristband.