Researchers have created a new skin patch that has powered a radio for two days using only human sweat.

The 'biofuel skin patch' uses the sweat to provide its power - meaning it could be used to charge up devices like phones in the near future, the New Scientist reports.

'If you were out for a run, you would be able to power a mobile device,' said Joseph Wang from the University of California, San Diego.

The 'biofuel skin patch' uses the sweat to provide its power - meaning it could be used to charge up devices like phones in the near future while people exercise (file photo)

His research team at the university have been working on the technology.

The biofuel patch is a few centimeters wide and sticks directly on the skin.

It works by using enzymes that act like the metals inside regular batteries, which are then powered up by feeding off the lactic acid found in sweat.

Researchers say getting enough power out of the patch has proven tricky, but they have now been able to extract 10 times more than previous attempts.

'We're now getting really impressive power levels,' Wang said.

The technology will be able to monitor an athlete’s performance but the main goal is to be able track human health.

It works by using enzymes that act like the metals inside regular batteries, which are then powered up by feeding off the lactic acid found in sweat (file photo)

The research, for example, could provide ways to manage the glucose levels in people with diabetes.

In a summary of their entry on the Energy and Environmental Science journal report, the researchers say it is the first example of powering a radio by a wearable biofuel cell.

'Successful generation of high power density under practical conditions and powering of conventional energy-intense electronic devices represents a major step forward in the field of soft, stretchable, wearable energy harvesting devices,' they wrote.