Health Farm

-- Sweat analysis brings new dimension to tracking exercise performance

Sweat could be the next big thing for device makers looking to capture more meaningful measures of our biological state during exercise.

Developers at Tufts University School of Engineering are developing a sweat sensor to track chemicals in sweat, including concentrations of sodium ions – an indicator of hydration – and ammonia ions, lactate, and acidity, which are related to muscle fatigue.

The postage stamp-sized sensor is attached to the skin using a fabric band aid to measure changes in sweat in real time.

Tuft researchers successfully tested the device on human subjects, monitoring electrolyte and metabolite response during maximum efforts on stationary bikes to detect variation in analyte levels.

The project is part of a larger strategy to make thread-based electronic devices that can be woven into fabric and act directly on the skin to track health and performance.

Tufts isn’t the only developer on the job. Scientists from the University of California, Berkeley, have designed a patch that can measure sodium in sweat to determine sweat rate directly from the skin.

Groups from Northwestern University, in Illinois, and the California Institute of Technology are also developing sweat sensors.

More recently, scientists from Penn State University designed a sweat sensing device that changes colour depending on the volume of glucose or sodium in sweat, and changes in acidity.