They needed to run an average lap of 77 seconds or less .
They posted a stunning record - beating time of two hours 14 minutes and 39 seconds , earning the tweeted congratulations of the great British athlete in the process .
Needing to run an average lap of 77 seconds or less , they posted a stunning record - beating time of two hours 14 minutes and 39 seconds , earning the tweeted congratulations of the great British athlete in the process .