No doubt it will come as a shock to learn that some advertisers make false claims. Sadly, I must report to you that exactly that the Federal Trade Commission has found Adidas/Reebok to have done just that with their claims about their Easytone shoes. The company claimed that their intentionally unstable shoes could help increase muscle tone, and that they had 20,000 hours of wear testing to prove it. But they never substantiated those claims, and the law suits started. Similar suits have been brought against Skechers and New Balance.
Today the FTC settled with Reebok for $25 million, and the company has removed claims about the shoe from their website. It will be interesting to see how Skechers and New Balance respond.
Personally, I feel that anyone who is naive enough to believe that simply wearing shoes will make you fit deserves to be ripped off, but I'm glad to see the FTC helping out.