Alexander Gerst SpaceTex

ESA astronaut Alexander Gerst on the International Space Station's fitness bike wearing SpaceTex during his Blue Dot mission in 2014.

Astronauts exercise 90 minutes a day to stay fit and preserve their bones and muscle while they live in space. After a heavy workout the first thing people do is have a shower but this is not an option for astronauts – they have to rely on wet-wipes.

To make matters worse, as gravity does not influence heat transfer in space, astronauts often report getting hot and sweating more during exercise. The SpaceTex experiment assesses two new fabrics to improve heat transfer and sweat absorption during exercise. The fabrics were also chosen for their antibacterial properties.

After exercise, Alexander Gerst filled in a short questionnaire to assess how comfortable the clothes are. When finished, his clothes were stored in a bag and returned to Earth to analyse the odour and air quality.

The results will be of interest to future astronauts who will smell less and exercise more comfortably, as well as sportswear manufacturers hoping to improve their products.