OK, gotta set the record straight on a couple of things. I really like Champion's "Jersey" shorts. They're thin, light weight cotton, and comfortable to work out in when I don't want synthetic.

two things:
1) if you want thicker material, and pockets, get the "rugby" shorts.
1) only the solid colors (black/navy) are 100% cotton. The grey and granite heather colors are mixed cotton polyester.

if you're not sure, check it out on champion's website first.
Personally, I prefer these lighter weight "jersey" shorts. I own both, and the thicker "rugby" shorts are good for walking and relaxing, but thick enough to be too hot for serious workouts.