Another Massachusetts shoemaker is being challenged for making health claims about its footwear.  A Florida woman, Valerie Bezdek, has sued Vibram USA Inc., based in Concord, accusing the maker of the FiveFingers running shoe of making misleading claims about health benefits. Designed to mimic the act of barefoot running, the minimalist running shoe has a shaped sole and a mesh top, with individual sleeves for each toe.  In its advertising, Vibram says the shoe improves posture and strengthens leg muscles. But the lawsuit says that using FiveFingers may be risky for runners.  “Indeed, running in FiveFingers may increase injury risk as compared to running in conventional running shoes, and even when compared to running barefoot,’’ according to a copy of the suit, filed in US District Court in Boston.  Get Business Headlines in your inbox:  The Globe's latest business headlines delivered every morning, Monday through Friday.  The Vibram suit follows several recent cases against Massachusetts shoe companies about how they market sneakers.  Last year, Canton-based Reebok International Ltd. refunded $25 million to customers after the Federal Trade Commission found it made deceptive claims that its toning shoes improved muscle tone. A suit filed in January 2011 alleged that New Balance, of Boston, also overstated the benefits of its toning shoes.  FiveFingers shoes have gained in popularity. Still, according to SportsOne Source, which tracks the sporting goods industry, barefoot-style footwear represents only 8 percent of the $6.5 billion running shoe market in the United States.  “This is a totally different manner of running,’’ said Matt Powell, an analyst with SportsOne Source, “and you need to be pretty dedicated to it.’’  There are similarities between the Vibram lawsuit and the Reebok case, but the Vibram claims differ, he said.  While Reebok promised firmer butts and toned legs as a result of wearing its toning shoes, he said the Vibram claims are more about the benefits of barefoot running, which Vibram claims are supported by scientific evidence.  “And there is ample evidence that training without shoes allows you to run faster and farther with fewer injuries,’’ the company says on its website.  Vibram, with corporate headquarters in Italy, is a 70-year-old company known for pioneering the use of rubber soles for footwear. It introduced its line of FiveFinger shoes in 2005.  Janine Pollack, one of the lawyers who filed the suit against Vibram, would not comment on the case. She was also involved in the case against Reebok.  Vibram did not return a call for comment.
Vibram USA Inc., which is based in Concord, is facing a class action lawsuit that challenges the company’s health claims about its minimalist FiveFinger running shoes. sneakers have grown in popularity along with the recent rise in “barefoot’’ running. The lawsuit challenges the shoemaker’s claim that its footwear helps reduce risk of injuries, improves posture, and strengthen leg muscles. The lawsuit follows a record-setting settlement paid by Reebok after the Federal Trade Commission complained that it was making false assertions about a brand of its shoes.