US researchers have engineered a line of "mighty mice" whose human equivalent would have similar abilities to the bicycling champion Lance Armstrong, according to research published Thursday. The breed of mice can run six kilometers (four miles) at a speed of 20 meters (yards) per minute for up to six hours without stopping, according to Richard Hanson, a biochemistry professor at Case Western Reserve University in Cleveland, Ohio. "They are metabolically similar to Lance Armstrong biking up the Pyrenees; they utilize mainly fatty acids for energy and produce very little lactic acid," said Hanson, the senior author of the article...