He ran a marathon on a treadmill while in prison. Now he’s eyeing Boston in April.

Keith Giroux started running as a way to pass the time while serving a prison sentence in Tennessee in 2015. Tired of watching television and playing cards, he would take laps in the outdoor yard.

When he was transferred to a facility in Massachusetts, his home state, Giroux lost his outdoor space — and his ability to smoke. He did, however, gain access to a treadmill.

“Months passed before I finally stepped up on it, but I instantly fell in love. Because I was no longer smoking, I found myself able to run much better than I had before. Running on that treadmill became my new favorite pastime. And it was so much healthier than previous ones!” Giroux wrote in a first-person piece published by Runner’s World in December.

He eventually ran a half-marathon (13.1 miles) on the treadmill. That’s when he developed a new goal: run a marathon on his prison treadmill at the same time as the 2016 Boston Marathon.

There were plenty of logistical obstacles. Giroux borrowed shoes from another inmate even though they weren’t running shoes. He had to run earlier than the actual Boston Marathon to make sure he was in his room for headcounts. And, since the treadmill turned off every hour, he broke the 26.2-mile run down into six segments to manage when he could turn the machine off.

Giroux described many of the challenges in a recent interview with WBUR.

But he did it. Giroux, who wanted to finish in four hours, needed four hours and 13 minutes to complete his first marathon.

“The clinician and others told me this was a great time, but I felt disappointed. I had missed my goal. Everyone slipped away and the officer told me I’d be allowed to take a shower before being locked back in my cell,” he wrote in Runner’s World.

Giroux was released from prison on Oct. 24, 2016, according to Runner’s World, and he ran the Myles Standish Marathon in Plymouth, Mass., a few weeks later. He finished in three hours, 24 minutes, this time wearing proper running shoes and clothes.

Now Giroux, 30, is chasing a new dream: Running the 2017 Boston Marathon. He has created a GoFundMe page to raise money for The Hopkinton Center For the Arts in Hopkinton, Mass. The Boston Marathon reserves some spots for charity runners, who meet qualification criteria.

“Many would ask why should they help me, a former convict, addict, and alcoholic? My answer to that would be because it is not about me. Yes, you would be helping me to live out a dream. But it’s so much bigger than that!” Giroux wrote on his GoFundMe page.

“It’s about spreading a message of hope to those who could use it most dearly. It’s about showing others who are stuck on the paths I used to travel that there is a better way of living. That no matter how far down the well they have fallen there is still light at the top, the well has not been sealed and they have the power to climb out of that. It’s about showing our children what dreams are made of, about showing them the possibilities are endless no matter what they come from and it is never too late, there is no such thing! This is about showing others that life is never so bad we should give up hope, or dreams, or happiness, and that we should never settle for the things that would make us less happy in life, or for the things that could ruin our lives.”

Giroux needs to raise $5,000 to have a chance at a spot in the Boston Marathon. He has raised more than $2,150 so far.

This story was originally published March 18, 2017 at 3:06 PM with the headline "He ran a marathon on a treadmill while in prison. Now he’s eyeing Boston in April.."