A new biosensor can alert endurance athletes when they’re about to “hit the wall’ or “bonk,” according to a study published in the American Chemical Society’s journal Analytical Chemistry.
The article describes the first human tests of the device, which attaches to the skin like a temporary tattoo (see the photo below) and flexes with body movements. The sensor, which was used on 10 volunteers, works by monitoring levels of lactate in athletes’ sweat.
Lactate—a form of lactic acid—is created when the body switches from “aerobic” respiration to “anaerobic” metabolism is an attempt to provide the muscles with more energy during exercise. While this effective for short periods, a buildup of lactate will cause extreme fatigue and can make athletes feel like they have “hit the wall.” Current methods of measuring lactate require blood samples and do not give instant results. For this reason, the biosensor is a vast improvement.
“Such skin-worn metabolite biosensors could lead to useful insights into physical performance and overall physiological status, hence offering considerable promise for diverse sport, military and biomedical applications,” the scientists said in a press release.
Sometime soon, these devices could be used to help soldiers, athletes and trainers more effectively monitor stamina and fitness. Future studies will focus on the correlation between sweat lactate levels with fitness, performance and blood lactate levels.