Most are some kind of poly, as are soccer jerseys--so they don't stay wet with sweat. I guess poly isn't the bad old stuff it once was.
Gee, thanks, Nanci, dammit---you got me to buy one. Those are NICE.
"My predominant feeling is one of gratitude. I have loved and been loved;I have been given much and I have given something in return...Above all, I have been a sentient being, a thinking animal, on this beautiful planet, and that in itself has been an enormous privilege and an adventure." O. Sacks