I bought fit flops on the advice of a friend, and I didn't know one was meant to wear them for short periods in the beginning. I wore mine all day, and I suffered from sore leg muscles and heavy pain on the bottoms of my feet. The leg pain resolved, but the bottoms of my feet are still worse than usual 4 days later. I went to the FitFlop Web site for information, and there was nothing. Otherwise, they are comfortable to walk in  and reasonably attractive. I'm about to try them again, though I wish for more specific information. The tags that come with the shoes offer advice not to wear them for long periods early on, but as is usual for me with tags I didn't pay attention. My bad. Later...these shoes caused my feet to hurt after wearing every time.