Cotton! I ride in cotton t-shirts with the arms cut off and regular cotton underpants under nylon running shorts and cotton socks.

Hang them over your bike or tent overnight they'll be fresh as newly washed by the morning. 5 days between washes no problem.

All you guys buying $100 smelly synthetic t-shirts that bacteria and funguses thrive in, crack me up. The sports industry has got you bent over!

My t-shirts cost like $5.

Flame away!!!