I wear moisture wicking t-shirts, bike pants/shorts and jogging shorts over the top for commuting. I use the t-shirts as a base layer now in Autumn, with long sleeve wicking t-shirts/MTB jerseys etc., under thin wind jackets. I have been using a whole lot of Decathlon clothing recently, including excellent ultra-light sweat wicking hiking t-shirts bought for about US $5.00. I think there's a Decathlon outlet in the US now as well; I love their pants, shorts and hiking clothes. I get their hiking shorts, also for about $5.00, and chop the integrated underwear section out of them, so I can wear them over the top of bike shorts for cycling or over non-chamois lycra shorts/leggings for walking and hiking.

Those shorts basically just hide any wild moose knuckles that may appear. The mere idea of a MAMIL can make some people break down and cry, rocking back and forth in the fetal position, while never once sparing a thought for your scrotal well-being. So if you're walking around families on river paths or hiking trails, or have to get off the bike for a coffee or coke, you can wear the shorts or keep them in a bike bag and slip them on when you stop, for politeness.