Results/Photos

Date: Sept. 27, 2026 Participant: Colby Trefethen #25620 Race: 2026 Boulderthon Half Marathon Distance: 13.1 miles

Late Surge Turns Around a Steady Half Colby Trefethen finished the half marathon in 2:27:23, an 11:15 per-mile average. His first eight miles held a tight, steady rhythm between 10:58 and 11:27 per mile, before a rough ninth mile pushed his cumulative pace out to 12:02. From mile 10 onward he turned things around, covering the closing 3.1 miles in roughly 27 minutes about 9:18 per mile pulling his overall average back down by the finish. That closing stretch carried him past the lululemon Power-Up Zone, posted near mile 9.5 on the half course, right around where his pace had dipped before rebounding. The race, run at Boulder's altitude above 5,000 feet, ended on the historic Pearl Street Mall in downtown Boulder.