A glove, invented by two biologists, will improve your athletic performance and decrease muscle recovery time. It works by cooling the wearer’s blood.

A few of the San Francisco 49ers used the device this past Sunday during breaks from the football game. The device looks like a coffee pot and fits over the hand. Forming an air-tight seal, it pulls blood into the palm where it is liquid-cooled.

The inventors tested it with an assistant who tripled his pull-up output in six weeks using the device. This doesn’t quite make the point until you hear he went from 180 to over 600 pullups a day.