UnderArmor seems to be getting the lions share of attention, but there are a lot of other choices if you're looking for something that wicks and fits well. Any running related store or manufacturer will have a lot to choose from. Reebok and Adidas in particular have a wide range of poly tops/bottoms that are on the looser side. In my experience, UA is preferred by people wearing pads (Lacrosse, football, hockey), while runners, skiers, and soccer players tend to go with other brands. I think tighter stuff gives a minimal amount of compression/support, but if you had an effed up knee or elbow, you'd probably have a special brace already. Personally, I swear by Patagonia capilene stuff. Their regular "long underwear" runs around $35 and the sizes favor most average builds. I picked up some of their running specific gear for triathlon training and have been very happy with the result. I'd watch out for stuff that's too tight. I think its been mentioned that tight stuff rides up, which is a pain if there wasn't much room for error to begin with. You'll notice this if you ever come up for a high parry (like a one) and there's a space between your jacket and a low waistband (if you wear warm-ups). Getting smacked on the love handle is only fun when there's a little romance involved.