I use this stuff on all my underarmor or dri-fit type stuff...undershirts, compression shorts, referee shirts, etc....anything that is performance/wicking fabric.
Amazon.com: Atsko Sport Laundry Detergent 34 Oz: Sports & Outdoors
I used to use
Amazon.com: Penguin Brands Penguin Sport Wash: Sports & Outdoors
until I found out that it was the exact same stuff and the Atsko stuff was a lot cheaper.
From one Amazon comment: The Penguin Sport Wash is identical to the Atsko Sport Wash and is actually filled by Atsko. Penguin is just their brand that markets to runners. They also have a version that they market to hunters/outdoorsmen. Every version is IDENTICAL.
I wash my under layers with the referee stripes and any other similar type of performance clothing....golf shirts, my wife's exercise clothes, etc. They're all the same basic type of fabric...none of them bleed and they all benefit from special treatment. Sometimes, it makes only a small load...but that is fine. No need to ruin the clothing to save a nickel. It also helps to have 5-7 of everything so you don't have to do the laundry often.
They ALL go in the dryer together on medium heat and NO dryer sheet. (Dryer sheets actually ruin the wicking behavior of the fabric...but, supposedly, that can be reversed with a few washings with no dryer sheet).
My pants and socks just go in the regular wash with other darks...but not with towels since towels are lint generators.