I'm scared. For the first time in 10 years, I'm legitimately scared for an expedition. I swore I would never do the Iditarod Trail Invitational (ITI). I'm not intimidated by the distance, but instead by the brutal elements and conditions of the Alaskan winter. You see, I don't belong in the cold. I have the unfortunate combination of poor circulation and active sweat glands. In the subzero temperatures of Alaska, this can be a deadly combination. I also have lung and breathing issues that have caused debilitating infections in cold or long races. — Rebecca Rusch

Exploration and pushing outside my comfort zone have been part of who I am my entire life. I've lived and preached the rewards of taking calculated risk for decades. What I realized this year, as I turned 50, is that it had been a while since I'd taken a really big athletic risk myself. I've done hard things, but haven't had that palms-sweating, heart-racing feeling about an expedition for 10 years. I realized I needed to really and truly challenge myself again. It was time to take on something bigger than I've done before. — Rebecca Rusch

Those were the Queen of Pain's words before embarking in her latest adventure. The organizers of the Iditarod Trail Invitational say that it "forces competitors to reach deep within themselves to persist while being besieged by relentless physical and mental challenges." The field in the 350-mile event included 28 bikers, 19 runners and two skiers.Today, Rebecca Rusch finished the 350-mile event with a time of 3 days 20 hours 55 minutes. Food and basic shelter were provided at checkpoints along the course, but it was otherwise self-supported and many riders including Rebecca had to sleep trailside when the exhaustion became too much. Temperatures were -23 degrees Celcius (-10 Fahrenheit) at the finish line.Congratulations to Rebecca and all of the other competitors. For those of you still out on the trail finishing up the 350-mile event or competing in the 1000-mile event, we wish you the best of luck! You can follow the live tracking here and see the full roster of athletes here