At Sunday’s Chicago Marathon, Sara Hall made her second marathon a memorable one, chopping an impressive 17 minutes off a challenging 2:48:02 debut earlier this year at the LA Marathon to finish 10th overall—and second American behind U.S. record-holder Deena Kastor—in 2:31:14.

Hall, who spent most of her time preparing for Chicago at altitude in Flagstaff, Ariz., and outside of Addis Ababa, Ethiopia, where she and husband Ryan recently adopted four sisters as their children, was a few minutes off her pre-race goal of 2:28 but managed to maintain her positioning in the second half of the race despite windy conditions.

“In the first half of the race, I was running with a good pack of guys that were clicking off steady miles in the high 5:30s,” Hall recalled. “However, after the halfway point that pack disintegrated and I was on my own to set the pace. Though I felt strong, I wasn’t able to maintain the same pace I did with company, and I could see my Lap Cues alerting me of miles in the 5:40s and some in the 5:50s. I could see my average pace creeping up every few miles and knew that if I wanted to run under 2:30 I would really have to start pushing it.”

Hall, who along with her husband is sponsored by Fitbit, shared some race-day data with us from her Surge GPS watch:

— Miles covered: 26.27 (How’s that for an impressive job cutting the tangents?)

— Average pace: 5:46 per mile

— Average heart rate: 172 bpm

— Calories burned: 1,397

— Calorie burn rate: 9.25 calories/minute

— Total steps taken during the race: 28,541

“I did my best—and in the end didn’t have a finishing time as fast as I thought I was capable of—but I am still pleased with the effort and feel I accomplished in Chicago what I set out to do: experience racing a marathon, see if I enjoyed the event and get a glimpse of my potential over 26.2,” said Hall. “I’m looking forward to tackling the distance again!”