Purchased a men's fitflop sandal for Christmas. Have used it every day and must say I do feel the difference when I walk. Something must be working as I do notice a that my leg muscles are quite tired at the end of the day. They are comfortable to walk in and very supportive. Tend to use them throughout the day. My only suggestion for improvement is to use adjustable straps as the present upper part of the sandal does loosen after awhile. However, still very happy with the purchase.