**Jeff Browning**, known throughout the ultrarunning community as "Bronco Billy," is one of the most durable 100-mile runners in the sport's history. Based in Flagstaff, Arizona, he has finished more than 200 ultramarathons and collected over 40 career wins, the majority of them at distances of 100 miles or longer.
His breakthrough at the sport's most demanding race came at the 2018 Hardrock 100, which he won at age 46 in 26:20:21 on the clockwise course through the San Juan Mountains of Colorado. That win made him the oldest Hardrock champion in the event's history at the time and cemented his reputation for late-career mountain form. He is a seven-time Hardrock finisher.
Browning's record at the 100-mile distance is built on consistency across very different courses. He won the HURT 100 in Hawaii in 2016 (21:22:00), the Hardrock 100 in 2018, the Bear 100 in Utah in 2019 (19:55:00), and the Moab 240 in 2022 (57:27:57), a 240-mile race through the Utah desert. He has also won the Bighorn 100 four times across his career.
He is the only man over 50 to be ranked in the top ten of UltraRunning Magazine's North American Ultrarunner of the Year, an honor he has received eight times. Outside of racing he coaches endurance athletes through his Go Bronco Billy platform.