Results/Photos

Date: Sept. 27, 2026 Participant: Rj Sonbeek #32518 Race: 2026 Boulderthon 10K Distance: 6.2 miles

Steady Effort Fades Late in a 10K Finish Rj Sonbeek covered the 10K in 58:39, an overall pace of 9:27 per mile. The race opened briskly with a 8:22 first mile, the fastest stretch of the day, before pace eased mile by mile 8:36 through two miles, 8:52 through three as cumulative time crept upward through the middle miles. By the final mile, split pace had slowed to 10:30, closing out a race that gradually gave back some of its early speed. Sonbeek's 10K started at 8:10 AM in Boulder, a city sitting above 5,000 feet of elevation, adding context to the effort behind that opening mile. Given the strong start, targeting a more even pace across the back half could be a useful focus for future 10Ks.