[Eugenia Gabrielov]

Elgin - here is a basic guide to active wear. My source is backpacking experience (hiking requires a lot of similar stuff) and a lot of running and tennis.

Synthetic fabrics are great for active sports - they dry quickly (especially if you sweat a lot when it's hot or want to take a quick shower under a sprinkler), and they wick away sweat (as somebody mentioned earlier). Go for 100% nylon, or something similar like that.

Other people have mentioned wearing underarmour leggings that go to the knee. These are very useful for comfort reasons (for both guys and girls I hear), and prevent chafing if you're running, hiking, etc. Wear them under shorts of any sort, and you're set. If you can get something like capilene (Patagonia and other outdoor brands sell it), especially for warm weather, you'll be cooling off your body as you go and it feels great. You can find these leggings anywhere from Target (not too expensive) to expensive outdoors stores.

I have pretty high quality expensive leggings that I use, Capilene Level 1, full length down to my ankles. I wore them hiking in 80 degree weather, and I run in them in 40 degree weather as well, so they're pretty versatile. Shorter ones are better for summer though

Have fun!