Results/Photos

Date: Sept. 27, 2026 Participant: Kieran Beirne #12281 Race: 2026 Boulderthon Marathon Distance: 26.2 miles

Strong Early Pace Holds Through Halfway Before Late Miles Slow the Finish Kieran Beirne finished the marathon in 3:47:37, an 8:41 min/mile pace. His race showed a clear shape: a fast, controlled opening through halfway, followed by a gradual fade in the closing miles. Through the first 14 miles, Beirne held a tight band between 7:20 and 7:49 per mile, reaching the midpoint near 1:53 elapsed. From there, pace slipped steadily, dropping into the 8:009:00 range by mile 18, before a tougher stretch between miles 19 and 22 pushed splits into the 10:0014:00 range. He steadied over the final four miles, closing with a 9:07 split into downtown Boulder. Miles 1 through 10 stood out as the strongest sustained stretch, averaging roughly 7:33 per mile. Given Boulders elevation above 5,000 feet, that early pace reflects solid pacing discipline before the marathons demands caught up in the back third.