The spandex Starfleet uniforms they wore on Star Trek: The Next Generation may have looked like the future, but they stank like nobody’s business. Costume designer Bob Blackman described the problem in an old BBC interview unearthed by Fast Company Design:
“Spandex retains odor, so there is a certain part where if you’re wearing them for a long period of time, you can’t really clean all the smell out, and it becomes a little bit annoying. And it also retains the odor of the dry cleaning fluid. It is, on a day-to-day basis, unpleasant.”
Ew. That’s just nasty. They were also very uncomfortable and gave the cast back problems which was why the uniforms changed in Season Three.