Results/Photos

Date: Sept. 27, 2026 Participant: Alfie Robertson #23438 Race: 2026 Boulderthon Half Marathon Distance: 13.1 miles

Negative-Split Surge Carries Him Into the Top 4% of the Field Alfie Robertson finished the half marathon in 1:35:50, placing 240th overall and 195th among men in a field of 7,223. After settling into the race around 8:14 per mile through the first two miles, he built into a strong negative split, trimming his pace steadily and closing the final four miles in roughly 6:34 per mile his fastest sustained stretch of the day. That surge lined up with the lululemon Power-Up Zone near mile 9.5, right where his splits dropped from 7:02 to 6:41 and kept falling toward a 6:26 closing mile. Given that Boulder sits above 5,000 feet, holding that kind of finishing pace after an even-effort start reflects well-paced racing. If there's one thing to consider for next time, it's testing whether a slightly faster start could convert some of that late speed into an even quicker overall time.