I did a challenge last November and made it to 3 min at the end of the month. It was tough but I did it. Once. Haha!
All I know is I'm never beating my daughter - she clocked 12 min, 19 secs in gym class. I knew she has some stamina, winning the family Festivus plank challenge after a nephew bailed at around 5 something, but I was still caught off guard by that number.