Four-time gold medalist Michael Johnson recovering from mini stroke

Olympic track great Michael Johnson says he is recovering from a mini stroke suffered last week.

The 50-year-old sprinter tweeted that he "rather surprisingly" was stricken with a transient ischemic attack, known as a TIA or mini stroke.

According to the Mayo Clinic, a TIA usually lasts only a few minutes and causes no permanent damage.

Johnson is a four-time Olympic gold medalist. At the 1996 Atlanta Games, he became the only male athlete to win the 200 and 400 meters at the same Olympics. He had held world and Olympic records in those events.