For most people, sweat is a major nuisance. It seems to do nothing but make you uncomfortably damp and smelly, and there’s a thriving industry behind products that aim to stop you from sweating or keep you from reeking after the floodgates have been opened.

But what sweat actually is turns out to be pretty cool – countless bacteria breaking down the proteins your body excretes, coupled with moisture to keep you from overheating. Well, the researchers at MIT’s Tangible Media group are trying to use the power of sweat to create BioLogic, a material that grows and shrinks based on changes in humidity and heat, which you may know as the exact conditions under which one sweats.

The technology harnesses the bacteria Bacillus Subtilis natto, or “natto cells,” which were discovered a thousand years ago by a Japanese samurai. They were discovered inside dry rice stalks, used for woven bags to carry soybeans, and essential in the fermentation of natto, a soybean-based Japanese dish. It wasn’t until a thousand years later that the cells were discovered to expand and contract based on atmospheric moisture, and their potential was fully realized.

These cells were printed into a biofilm and attached to a spandex suit to use the biological processes of dancers to control the bacteria. The cells curled up when exposed to a bit of humidity, and opened completely when exposed to more, allowing for fabric that breathes where a person might be at their sweatiest. The result is a fabric that effectively shapeshifts based on the wearer’s sweatiest areas, and opens up to allow those areas to breathe. 

MIT is now growing these cells by the billion, envisioning biological interfaces: specifically grown actuators and sensors. Someday, they might even be able to include bioluminescent bacteria into the fabric.

BioLogic’s would be very effective in designing next-generation active wear. Picture it: during a workout, the sweatier parts of the body would be given room to breathe, preventing users from overheating during a workout. Athletes and dancers could benefit from this the most; during the game or show the bacteria-laden fabric would constantly be moving aside to help the body cool off more effectively. I could see this working for the military as well, soldiers might wear this under their uniforms and protective gear to keep them from overheating.