I have a thumb-sized flashlight for navigating to the bathroom in the darkness, so I like a pocket in my sleepwear, and none of my underwear has a pocket! So I have lightweight nylon shorts for sleeping. I use a polypro t-shirt (GoLite), too, because I don't like to transport nighttime perspiration into the morning walk. My walking clothes tend to acquire increasing aroma as the weeks pass, but I always have something semi-clean for sleeping (as long as I wash it every few days). Both shorts and shirt can double for walking, but I have never had to use them for it, though I came close when I left my second pair of convertible pants on the clothes line!