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Jonathan (Jon) Clinthorne, PHD


Jonathan (Jon) Clinthorne is an ultraendurance athlete with a doctorate in Human Nutrition from Michigan State University. Growing up as a competitive swimmer, the idea of training for 2 hours a day when training for ultramarathons did not seem outlandish, so he jumped right in. During college he decided to pursue nutrition as a full-time career, falling in love with the biochemistry of ultraendurance athletics. He has run over 50 ultramarathons, including twelve 100 mile races. Jon has self-experimented with just about every nutrition approach and over the years found what works and doesn’t work. He specializes in evidenced based nutrition counseling that is combined with his deep practical knowledge of sport. His philosophy is that there is no “one size fits-all” approach to endurance nutrition and instead prefers to work with his clients to determine which evidence-based approach will fit them best. He serves on the Board of Directors along with being the Course Director for the High Lonesome 100. When not running you can find Jon skiing or hiking in the mountains of Colorado.


  • Nutrition counseling
  • Ultramarathon
  • Marathon
  • Half Marathon


  • BS – Human Biology, Michigan State University
  • PhD – Human Nutrition, Michigan State University

Running History & Awards

  • Twelve 100 mile finishes
  • 50+ ultramarathon finishes
  • 35 top-ten finishes
  • 3 course records