A new device, a wearable patch, made by an engineering team at the University of San Diego has been said to accurately monitor both heart rate and various biochemical information while being worn during exercise.
Flexible and Wearable Patch
A report of the team’s work has been recently published in Nature Communications and explains that the device, called the Chem-Phys patch, is a thin polyester sheet, which is flexible and contains a small screen printed chip to record various biochemical data. This data can then be sent wirelessly through Bluetooth to a nearby device for analysis and inspection. The device, in testing, has been worn on the chest around the sternum area.
The device records information of the wearer’s heart rate activity (EKG – electrocardiogram) and levels of lactate, a chemical, which correlates with physical exertion.
One of the greatest design challenges in developing an apparatus like this is making sure that the various readings do not meddle and invalidate the other readings. Keeping the mechanism small and unobtrusive to wear is obviously important, but to make sure that it is not too compact as to lead to cross-channel interference. To combat this, the heart monitor and lactate reader are about an inch and a half (four centimeters) apart which seems to have solved the riddle.
The lactate sensor functions by sending a low voltage and recording electrical current between its electrodes. This current is able to pass through the sweat (a conductor) generated by exercise, but this sweat can also cause malfunctions with the EKG readings, so they developed a layer of water resistant silicone to keep the EKG dry but not the lactate sensor.
They stated in tests looking at fifteen to thirty minute exercise sessions the heart rate information was said to be as equally accurate as a traditional heart rate monitor.
The projects leads, Professor Joseph Wang, a nanoengineer, and Patrick Mercier, professor of electrical engineering at UC San Diego Jacobs School of Engineering, stated they were looking to move forward the industry by having one device performing multiple functions, “One of the overarching goals of our research is to build a wearable tricorder-like device that can measure simultaneously a whole suite of chemical, physical and electrophysiological signals continuously throughout the day,” Mercier said. Current devices tend to have a single function, measuring for example, only heart rate or steps taken.
Obviously athletes, looking for greater feedback from their training sessions, are a clear target market. Sports people, especially those with lofty ambitions, devour this information to help in tracking progress and looking for the slightest edge on competitors. The developers have also speculated that doctors wanting to monitor heart rate data for patients at risk of various cardiovascular problems could easily find use for this equipment.
Wearable health monitoring devices are certainly increasing in popularity at the moment but they are experiencing teething problems, especially with heart rate monitoring. The Apple Watch has not been a super commercial success, (outside of the usual Apple fanboys), and Fitbit is facing legal scrutiny over the accuracy of its proprietary heart rate monitoring technology.
For the Chem-Phys patch, the developers are looking at ways of increasing the amount of data the patch is able to capture (again battling the danger of various sensors interfering with each other). Other chemical markers on their radar include monitoring magnesium and potassium. We wait further development with anticipation, as the benefits of having easily accessible data of this type are intriguing.