Career
Mackey has set course records at many significant national ultra-distance trail running races, and spent several years adventure racing nationally and internationally. In running from one side of the Grand Canyon and back, also known as the rim-to-rim-to-rim (R2R2R), Mackey holds the former record of 6:59:57, which has since been lowered by Rob Krar. Mackey also holds speed climbing records in the Boulder, Colorado, area, including the fastest round-trip time climbing and descending the Third Flatiron from Chautauqua Park in Boulder.
He is a physician assistant in emergency medicine.
