When a 54-year-old has one foot on the ground and the other about a foot above her head, people generally call the paramedics. For Linda Donner of Barrington, that's just one of the moves she has mastered as a sixth-degree black belt in karate. Last month, Donner, owner of the Traditional Karate Organization, a martial arts and fitness studio in Lake Zurich, brought home a bronze medal for the United States in the World Union of Karate-Do Federations in Fort Lauderdale, Florida.