How’s this for extreme? Ellyn Brown recently ran three miles up a 3,500 mountain in 54 minutes and 57 seconds.

At 54 years old, she became the first woman in the 19-year history of the Bird Ridge Race to run it in a time equal to or less than her age.

She’s as tough as they come. Find out why she runs races as long as 24 hours long and competes in grueling snow shoe races.

Plus, find out why she thinks turning 50 was one of the best things to ever happen to her.