Toning footwear were all the craze a decade ago. The promotors of those footwear made unbelievable claims for them. These claims varied from helping weight reduction to eradicating cellulite to sculpting the butt to fixing sore backs. The footwear were built with a rocker on the sole aimed at increasing muscle activity to obtain those supposed benefits. Unfortunately, the evidence did not support the claims and there was a great deal of litigation from dissatisfied customers and many manufacturers had to negotiate multi-million dollar settlements with the Ftc.
Although all that is in the past you can find some of these types of footwear available and they still do have certain support from those people who are knowledgeable about them. The footwear do alter the way that you walk and for some individuals that may sometimes result in an improvement in some things like sore backs. Similarly, it might make some people with low back pain feel more painful. There is a lot of effort being directed at studying precisely what these shoes actually do and precisely who can benefit from them and who might be hurt by them. Each person will likely react in a different way the shoe.
Foot doctors seem to especially like these sorts of toning shoes because of the kind of patients that they see. The rocker sole nature of the footwear means they especially great for those with a sore great toe joint, as with these shoes the joint doesn't have to move as much. However, while that might be useful for that joint it will put more pressure on the ankle joint so could create or make more painful issues at the ankle joint. It was problems like this that led to the legal issues in the past and need to be carefully considered by anyone suggesting or using these shoes. They do have their uses and they may help for the right people with the right condition.