S.F. man’s 7 days running: 7 marathons, 7 days, on 7 continents

Tim Durbin, of San Francisco, completed the World Marathon Challenge on Friday, finishing the last of seven 26.2-mile worldwide races in Sydney. Tim Durbin, of San Francisco, completed the World Marathon Challenge on Friday, finishing the last of seven 26.2-mile worldwide races in Sydney. Photo: World Marathon Challenge Photo: World Marathon Challenge Image 1 of / 4 Caption Close S.F. man’s 7 days running: 7 marathons, 7 days, on 7 continents 1 / 4 Back to Gallery

Running a marathon is not easy. Running seven in seven days on seven continents is really not easy, as Tim Durbin can tell you.

The San Francisco resident completed the World Marathon Challenge on Friday, finishing the last of seven 26.2-mile worldwide races in Sydney.

“And done!” he posted on Twitter, after running the last race in four hours 55 minutes.

The feat was an extreme test of fitness and willpower that Durbin, 31, said he put himself through as part of a lifelong mission to log 24,901 miles — the distance around the equator. Each of the past seven days he spent five to six hours running, sometimes twice that much time traveling, and what was left over trying to sleep.

Arrived safely back in Chile! Leg 1 down in 4 hours 36 minutes. Leg 2 starts less than 19.5 hours after leg 1 began. Nap time. Thanks for everyone's support. A photo posted by Tim Durbin (@24901experiences) on Jan 17, 2015 at 4:04pm PST

He said the quick turnarounds caught up with him before his fifth race in Marrakesh, Morocco.

It “was the second in less than 24 hours and started seven hours after finishing Madrid,” the management consultant wrote in an e-mail to The Chronicle. “It was cold and drizzled a bit as well.”

Durbin was one of a dozen runners taking part in the seven-marathon challenge and the only American. The contest took him to Union Glacier, Antarctica; Punta Arenas, Chile; Miami; Madrid; Marrakesh; Dubai, United Arab Emirates; and Sydney.

He plans to relax in Australia for another week before returning home.

Dean Karnazes of Ross, who ran 50 marathons in 50 days in 50 U.S. states in 2006, said the hardest thing about running consecutive races is the total lack of recovery time. Many runners dial it back for a month after finishing a marathon. Durbin and Karnazes got a few hours.

52.4 miles (2 marathons) in 25.5 hours deserves a recovery drink and a good nights sleep! A photo posted by Tim Durbin (@24901experiences) on Jan 17, 2015 at 7:14pm PST

Then there’s “extreme and extended sleep deprivation,” Karnazes said. “Sleep is important in the recovery process, and you just don’t get a lot of it.”

Durbin said most of his sleep was on the planes. He was able to fly business class, with one exception: the Ukrainian cargo jet that took him to base camp in Antarctica. Temperatures there were well below zero.

The marathon accomplishment set Durbin back nearly $40,000, which he said he paid for with savings. He’s been fundraising, too, trying to make $77,777 for the V Foundation for Cancer Research. Several of his family members have battled the disease.

While Durbin is a stellar athlete who swims and skis, he hasn’t run competitively at the top level and didn’t intend to set any records this week.

“When thinking about the World Marathon Challenge during the numerous 'lonely’ hours spent running or walking around San Francisco in 2014, I realized that even if I do finish 'last’ I won't be finishing last at all,” Durbin wrote in his online journal. “I dared to do something that most people view as impossible.”

Kurtis Alexander is a San Francisco Chronicle staff writer. E-mail: kalexander@sfchronicle.com Twitter: @kurtisalexander