Jim Walmsley

Jim Walmsley
Personal information
Born (1990-01-17) 17 January 1990
Phoenix, Arizona, United States
Height1.81 m (5 ft 11 in)
Weight70 kg (154 lb)
Sport
Country United States
Event(s)Half-marathon, ultramarathon, trail running
College teamAir Force Academy
TeamHoka One One
Achievements and titles
Personal best(s)1500m: 3:48.16
3000m st: 8:41.05
5000m: 13:52.87
10,000m: 29:08.88
½-marathon: 1:04:00
Marathon: 2:15:05
100km: 6:09:26

Jim Walmsley (born January 17, 1990) is an American long-distance runner. An ultra-trail specialist, his wins include the JFK 50 Mile in 2014, 2015 and 2016, the Lake Sonoma 50 in 2016 and 2018, the Tarawera Ultramarathon in 2017, and the Western States 100 in 2018, 2019, 2021, and 2024. He holds several course records, including the Western States 100, set in 2018 and further improved by 21 minutes in 2019. In 2023, he became the first American man to win the Ultra-Trail du Mont-Blanc.

Walmsley has set 7 Fastest Known Time running records, including the speed record for the 44-mile Rim-to-Rim Grand Canyon crossing in 2016.

Sponsored by Hoka One One, Walmsley was named UltraRunner of the Year for four years in a row - 2016, 2017, 2018 and 2019. In addition, he qualified and ran in the 2020 Olympic trials in the marathon with his 2019 qualifying performance at the Houston half-marathon. While competing in the Hoka One One Project Carbon X 100K Challenge on May 5, 2019 he set a new world best for the 50 mile distance, completing it in 4:50:07 (besting Bruce Fordyce's previous 36-year old record by 14 seconds). Walmsley won the World Long Distance Mountain Running Championships in 2019.

In 2023, Walmsley won Ultra Trail de Mont Blanc UTMB in a course record of 19:37:43 becoming the first American man to win the race.