Something was wrong with Tina Sprinkle’s hip—but not her business. Tina Sprinkle, the owner of Pilates 1901, could tell something was wrong. She had undergone a hip replacement less than three years ago, but the pain in that joint never completely went away. The staff at her exercise studio even gave her the nickname of the Pilates Pirate because of the way she walked, as if she had a peg…

Every year, Time magazine publishes its list of the 100 most influential people. The 2012 edition included names like Apple CEO Tim Cook, actress Viola Davis, U.S. Sen. Marco Rubio and 97 others who have made a major impact on the world. It’s easy to think that “being influential” is only for the famous, but that’s not true. Everyone has influence. By definition, influence is simply the capacity to affect…