Women who wear high-heeled shoes often experience discomfort and pain. Robert Csapo, from Manchester Metropolitan University (United Kingdom), and colleagues have found that women who have worn high heels for years experience alterations of the anatomy of the calf muscles and tendons. The team enrolled 80 women, ages 20 to 50 years, who had been wearing heels of at least 2 inches (5 cm) almost daily for two years or more. Ultrasounds revealed that the women had calf muscle fibers that were 13% shorter, while MRIs showed the Achilles’ tendon was stiffer and thicker, as compared to women who wore flatter shoes.  The team concludes that:  “Long-term use of high-heeled shoes induces shortening of the [Gastrocnemius medialis] muscle fascicles and increases [Achilles' tendon] stiffness, reducing the ankle's active range of motion, “ and suggests these two anatomical changes may be primarily responsible for women’s pain and discomfort experienced with wearing high-heeled shoes.