The odor problem with synthetic clothing has been solved as well. Fifteen years ago, synthetic workout clothes stank after you owned them for a couple of months. People shared all kinds of tips online for removing the stink or delaying its development, and I tried many of them, but nothing really worked. Now none of my workout gear stinks after being washed. I even own a synthetic shirt that I've worn day after day without washing on multiple backpacking trips over years, and it doesn't retain any odor after washing.