Derek Mitchell knew he was in last place. 

“I hadnt even gotten to the first mile, and they were already opening up intersections behind me,” Mitchell said. I tried to put it out of my mind.”

But Mitchell stayed focused on his goal of completing 3.1 miles at the Big 12 Run in Kansas City, Missouri, where he lives. At 570 pounds, it didn’t matter what the clock read at the finish. He just wanted to reach the finish.

The Big 12 Run wasnt Mitchells first attempt at the distance. He tried to do one last year but had to drop out.   

That took me down a notch or two, Mitchell said.  

So on January 1, Mitchell, who weighs 570 pounds, decided to cut soda out of his diet, eat healthier, and go for daily walks, starting with just one mile a day. Then his sister, a marathon runner who races frequently, suggested he sign up for a 5K.  

I decided that, starting in March, I would do at least one 5K each month for the rest of the year, Mitchell, 34, told Runner's World Newswire. Ive already been talked into two in May. I want to try and lose five minutes off of each one, but at this point, I just want to finish.

Mitchell, who is a regional support technician for Cabelas, the hunting and fishing gear retailer, chose the Big 12 Run, an event that also hosts a 12K which shares the 5Ks start and finish lines, to launch his streak. 

By the end of the year, I'll have finished 11 5Ks, which, just thinking about [the fact that] I'll have walked 55 kilometers is a little daunting. But I'm looking forward to it.

Mitchell said he wants to shed at least 250 pounds along the way.      

With that in mind during the race, Mitchell kept pressing forward alone for the next mile and a half—save for a police car shadowing him. Just before the 2-mile mark, the 12K runners who had split off earlier in the race, rejoined the 5K runners on the course.

I’ve volunteered at several races before, and there’s this one guy that I love seeing—he’s a paraplegic who uses a handbike—who I saw zip by as a part of the 12K group, Mitchell said. I was like, ‘Wow, I’m not alone anymore!’

Then the other 12K runners began cheering Mitchell onward.

It was really cool because a lot of them were exhausted, but nearly every one of them gave me high-fives and told me, ‘Good job!’” Mitchell said. It was really encouraging that everybody was so awesome.

Coming down the final stretch, Mitchell's feet and knees were killing him.

As soon as I saw that finish line and heard everybody yelling, all the pain that Id been feeling up until that point vanished, Mitchell said. I booked it. I couldnt go as fast as Id wanted to because Id already lost some weight and my pants started falling down. But it was just amazing. He finished in 1:27:44.

After the race, NBC2 News picked up his story. The article and video sparked a flood of messages from supporters to Mitchells personal Facebook profile, which inspired his sister to create a community page for him

Even before the race, Mitchell posted updates about his daily walks, inviting others to join him. Now strangers around the country are saying theyd like to race a 5K with him if hes ever in town.

Originally, I started this for myself because I needed to get healthy, Mitchell said. But it's amazing the way you can inspire people to get up and get moving just by doing something simple like finishing a 5K.  

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