All our non-crease items are made of a 4-way stretch fabric that is synthetically combined with spandex. The advantages of this fabric are wash-and-wear, fast-drying, and you don't even need to iron it, actually don't iron it, that's a bad idea.
It's also moisture-wicking, which as you may or may not know has two fantastic jobs:
It quickly moves (wicking) sweat to the fabric's outer surface and
It drys rapidly. Yay 12 hour shifts she says sarcastically.
This is definitely a must-have for those on the run.