In 2014, ESA astronaut Alexander Gerst wore SpaceTex shirts on the ISS for six months; their fabric data helped inform clothes for future Mars crews

Sweat is already a nuisance enough to deal with while jogging on a treadmill at your local gym. Now try sweating while you are 250 miles above Earth, with no gravity to help drain it away. During his Blue Dot mission aboard the International Space Station in 2014, ESA astronaut Alexander Gerst wore specially designed shirts while exercising on the station's bike as part of SpaceTex, an experiment that investigated how clothing manages heat and sweat in microgravity. Gerst's mission lasted 165 days, from May 28 to November 10, rather than a full six months. On Earth, gravity pulls sweat downward, while airflow helps it evaporate. In microgravity, these processes work differently. NASA explains that the lack of natural convection in space affects how heat is transported and how clothing interacts with moisture. Astronauts have also reported sweating more during exercise in space than they do on Earth and have described the sensation of heat surrounding the body.

Why was fabric science more crucial in space than on Earth?

A warm, moist environment can provide favorable conditions for bacteria and other microorganisms to grow. In space, this can become a practical health concern because astronauts cannot simply wash their clothes whenever they become sweaty, while ventilation also works differently from that in a home environment. This is where the SpaceTex research became particularly relevant. The materials tested during the experiment were selected for properties including antibacterial performance, drying behavior, and their ability to help manage heat and moisture during physical activity. NASA describes SpaceTex as the first clothing physiology experiment conducted in microgravity.


For Gerst, the testing involved the Cycle Ergometer with Vibration Isolation and Stabilization, a stationary bicycle designed for use aboard the space station. The sessions allowed researchers to compare high-performance fibers with conventional cotton clothing in terms of comfort during exercise. The resulting information, together with physiological data gathered during the experiment, was later identified by NASA as useful for developing clothing for future long-duration missions, including possible crewed journeys to Mars.

How space-tested fabrics could shape future clothing

Long-duration spaceflight creates a clothing challenge that is easy to overlook. Astronauts cannot simply pack a new outfit for every day of a lengthy mission. Water is limited, laundry facilities are generally unavailable, and storage space is valuable, so future clothing has to balance comfort, durability, and hygiene. NASA notes that space textiles will need to manage heat and sweat while supporting the body's natural thermoregulation and helping limit microbiological contamination, particularly as missions become longer.

The same questions researchers explored in orbit, such as how to move sweat away from the skin, manage moisture, and maintain comfort during exercise, are among the issues sportswear companies consider when developing running shirts, base layers, and workout gear for use on Earth. Moisture-wicking fabrics and antimicrobial treatments were already established in commercial sportswear before SpaceTex, so the experiment should not be presented as the origin of those technologies. Instead, its value lies in examining how textile properties perform under the unusual physiological and environmental conditions of spaceflight.

Firefighters, miners, and members of the armed forces could also benefit from materials designed to manage sweat and dry quickly, since these professions can involve strenuous work in hot or demanding environments where clothing performance matters. NASA has reported interest from sportswear manufacturers in applying findings from space textile research. A modified polyester material developed using principles associated with this research was also developed for use by the Swiss armed forces. Rather than being a future possibility, that application belongs to the later development and deployment of military clothing systems.

The SpaceTex story therefore offers a more grounded example of how space research can inform textile development without suggesting that modern moisture-wicking clothing originated in orbit. The experiment examined a problem that becomes especially difficult in microgravity: keeping astronauts comfortable while their bodies produce heat and sweat during exercise. What researchers learned from Gerst's testing could contribute to the design of clothing for future missions, while also adding to the wider body of knowledge about how fabrics manage moisture, heat, and comfort during demanding physical activity.