The logistics alone for Durbin and his big adventure are a nightmare. He starts in Antarctica on Jan. 17, then it's onto Chile, followed by Miami, Madrid, Morocco, Dubai and he ends up in Sydney, Australia.
Is this guy insane?
"That's usually the first question all my friends ask me... why are you doing this?" Durbin said.
He has his reasons. Durbin explained, "I just saw it as another mental and physical challenge that I could take on and prove that an average person like me can actually do what a lot of people think is impossible."
At least this insanity is for a good cause.
"I'm raising money specifically for the V Foundation for cancer research. To follow along the seven marathons in seven days on seven continents, I'm trying to raise $77,777 for the Jimmy V Foundation," Durbin said.
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He ran his first official marathon two years ago in Antarctica and has been training for the past eight months. His biggest concerns are the jet lag, sleep deprivation and eating most of his meals on the airplane.
"It will be quite a challenge of basically land in an airport, going and running, going back to the airport, getting on a plane and do it all over for seven straight days," said Durbin.
His wife, Tracy, is a triathlete and Durbin's biggest supporter. He said, "She will meet me in Sydney. Yeah, the last one. She'll actually be sitting at a resort for the week that I'm actually running it."
Durbin is the only American running in the event and is funding his own trip. He looks forward to getting to know his fellow marathoners in the 168 hours spent together. They have eight hours in each continent to complete each marathon and Tim is determined to finish all seven.
"The fact that I'm raising money for cancer research will definitely elevate the sense of personal accomplishment for myself as well," Durbin said.
If you would like to follow Tim Durbin on his journey or make a charitable donation for his cause, click here for more information.