51.   This individual was a marathon runner.

52.   This change gives marathon runners the added energy they need to run long distances.

53.   Thompson, a cardiologist at Hartford Hospital in Connecticut, is a marathon runner who, despite his best efforts, has never been able to grow big muscles.

54.   To be a real good marathon runner you need some years to prepare.

55.   Today, when scientists see marathon runners, they say they are reminded of this past and how little is still known about it.

56.   Today, America has no notable marathon runners.

57.   Woods is as much an anomaly as the marathon runner who sprints out of the starting blocks.

58.   World-class marathon runners possess more slow-twitch muscle fiber.

59.   Organizer Sachio Hobara, himself a marathon runner, said the main goal of the run was not competition.

60.   Polish marathon runner Antoni Niemczak has been suspended for three months after failing a drug test, the International Amateur Athletic Federation said Wednesday.