King, 32, of Bend, Ore., conquered the 50.2-mile course — which started in Boonsboro and finished in Williamsport — in 5 hours, 34 minutes and 58 seconds. He averaged 6:42 per mile to top the field of roughly 1,000 runners.
Trent Briney, 34, of Boulder, Colo., finished second in 5:37:56, also dipping under the previous course-record time of 5:40:45, set last year by David Riddle, who finished third this year in 5:45:13.
“The oldest, the biggest — it’s one of those classic all-American ultras,” said King of the JFK 50 Mile, which he ran for the first time Saturday. “It feels special just to be here for the 50th, and not just to be here, but to win and get a course record, too.”
Greenwood — a 33-year-old British citizen who lives in North Vancouver, British Columbia — was the top female in 6:11:59 as she shattered the previous women’s record of 6:29:21, set in 2009 by Devon Crosby-Helms. Greenwood, in her debut at the race, also became the first non-U.S. citizen to capture a JFK victory.
Emily Harrison, 26, of Front Royal, Va., also went under the old mark, finishing second in 6:17:16.
“This is big,” Greenwood said. “To get the course record — and it was a solid course record — I knew I’d have to have a good day.”
At 15.5 miles — at the conclusion of the rugged Appalachian Trail section of the race — Greenwood was in the lead, a little more than 2 minutes ahead of Harrison, who was running her first ultramarathon.
Harrison, a standout 2:32 marathoner, immediately began to close the gap on the flat C&O Canal towpath. She passed Greenwood at mile 21 of the race and built an 80-second lead on her by mile 27.
“The goal going in was to win and get a course record,” Harrison said. “At that point, I felt all right, and I thought I might have a chance.”
Greenwood, a world-renowned ultramarathoner who owns the course record at the prestigious Western States 100 Mile Endurance Run, didn’t seem overly concerned about the deficit at that point in the race.
“I was not going to get pulled into running too fast, knowing there were still so many miles to go,” she said. “I just had to run my race and my pace and wait it out a little.”
By mile 31, Greenwood was back in the lead, this time for good as she gradually pulled away.
“The women’s race was everything we hoped it would be — the world-class marathoner stepping up and the world’s best 100-mile runner stepping down, and a classic back-and-forth battle ensued,” race director Mike Spinnler said.
With Harrison behind her, Greenwood set her sights on the frontrunning men and ended with a 10th-place overall finish.
“To get top 10 is pretty cool,” she said. “That’s not my focus, but toward the end that was some incentive.”
In the men’s race, Riddle, 31, of Cincinnati, didn’t give up his title without a fight. He came off the Appalachian Trail at 15.5 miles in the lead, up 15 seconds on King, while Briney was nearly 8 minutes back in sixth.
But Riddle was no match for King and Briney, both sub-2:15 marathoners, on the 26.3-mile stretch of towpath, which both covered in less than 2:45 on Saturday.
It didn’t take long for King to build a sizable lead or for Briney to improve his position in the field. By mile 30, Briney had a firm grip on second place, trailing King by about 4 minutes.
“I was dreaming coming up the towpath, thinking, ‘Maybe,’” said Briney of his pursuit for victory in his first 50-mile race. “I didn’t expect to beat Max, but you never know. Anybody can throw up, anybody can have to walk, anybody can cramp.”
By mile 46, King’s lead over Briney had increased to 5 minutes, with only 4.2 miles of rolling paved roads separating him from the finish line in Williamsport.
“I do well being chased like that,” King said. “But those last 4 miles, I was hurting pretty bad. But at that point, I kind of knew I had it and had the record, and I just kind of coasted in (for the 3-minute victory).”
Spinnler was more than impressed.
“The level of competition here has never been better in the 50-year history of the JFK,” he said. “I honestly believe that Max King is the best 50-mile runner on the planet.”