Asked by: Albert Gordon, Gibraltar
The record is currently held by the Russian cosmonaut Valery Polyakov, who orbited Earth continuously for over 14 months (437 days and 18 hours) between January 1994 and March 1995.
During that time, he followed a strict regime of exercise to combat the muscle and bone degradation that notoriously follows long exposure to weightlessness. And it seems to have worked: the fiftysomething cosmonaut returned to Earth seemingly none the worse for wear.
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