British ultrarunner Sarah Perry has set two records at the Backyard Ultra world championships in the U.S.
Perry, a maths teacher from Cockermouth, Cumbria, set a new women's record of 95 laps -- which is almost 400 miles -- beating the previous women's record of 87 laps, held by American Megan Eckert.
The 34-year-old also beat the UK record, exceeding Matt Blackburn's previous best of 87 laps.
Backyard Ultra is a race that involves running laps of a 4.167 mile course (known as yards) on the hour, every hour for as long as the individual can manage. As the hours and days pass, runners drop out until the last person running and still within the cutoffs is declared the winner.
Perry qualified for the individual world championships after claiming the UK women's record last year. She was one of four women out of 72 entrants in Bell Buckle, Tennessee. Eckert completed 92 laps, as Perry continued for another three, covering 395 miles in 95 hours before retiring with a back issue.
"I've got mixed emotions," Perry said. "I'm quite disappointed that my back went when everything else was working so well. I had it in my legs and my head on reaching 100 laps, something I was really fixed on, but that's ultrarunning.
"It's going to take a while to process it all. I just need to catch up on sleep and then process what I've achieved."
Perry took naps for around 5-10 minutes at a time in a tent and refuelled between laps and supported by her partner Luke.
"I love entering races or challenges that I'm not certain I can complete," Perry told the BBC. "I mastered doing a slightly faster night lap then coming in and closing my eyes for 5-10 minutes. Sleep deprivation wasn't really an issue. You feel fine once you're running and then you suddenly realise how bad you feel [when you stop]."
Australian Phil Gore won the race with 114 laps, five short of his own men's record.
The race was created by Lazarus Lake, who also created the Barkley Marathons, which is held in Frozen Head State Park, Tennessee. Earlier this year, British runner Jasmin Paris made history by becoming the first woman to complete the race.