Mildred Gray bought a pair of Skechers Shape-Ups hoping they would build her leg muscles because of their unusual rounded arch, but after using them for awhile she was disappointed.

Gray had no idea that Skechers now has to pay $40 million to customers who purchased the shoes as part of a settlement with the Federal Trade Commission. The FTC says the shoe company's claims that the shoes would tone your legs and butt were unfounded.

"They really did a number on my knees and I switched from running to walking because of that and they were horrible," Gray said. "I literally could not use those shoes and they cost me pretty good."

While Skechers will have to pay, they're not backing down from their claims that the shoes can tone a person's body. On their website Sketchers says: "Sketchers denies the allegations and believes its advertising was appropriate, but has decided to settle these claims in order to avoid protracted legal proceedings."

For more information on the settlement involving Shape-Up shoes, visit www.ftc.gov