The E.R. actor will be participating in the ING New York City Marathon Nov. 1 to raise funds for Shoe4Africa, a non-profit organization that donates shoes to Kenyan athletes and aims to build the largest public children's hospital in Africa.
"There's no pediatric education and medicine in sub-Saharan Africa," Edwards, 47, tells PEOPLE. "One hospital there has always had a dream of having a children's hospital so we're really hoping to achieve that dream. They need the funding and we're telling their story."
Edwards, who serves as Shoe4Africa's chairman, first became involved with the organization 3½ years ago when he took an around-the-world trip with his wife and four kids. The family stopped in a rural part of Kenya to attend one of the organization's running events, where 2,000 women participated and also learned about AIDS awareness, testing and education.
"It was an incredible event that was all done through the joy and support of running," says Edwards. "I just became fully committed."
Hospital-Themed OutfitsTo prepare for his 26.2-mile, all-borough trek in November, the actor has been training his body for more than two months while also getting his mind ready.
"It's mostly psychological. I'm doing an 18-week program and I've already been running for five days a week for 2½ months," he says, "which is even more reasons why people should sponsor me!"
In a sea of 40,000 runners, fans may still be able to spot Edwards. He says his group will be donning bright yellow scrubs tops to "keep with the hospital theme."
And his goal for the race?
"Everybody is going to run whatever time they're shooting for, and we've raised $450,000 so far but we'd like to reach the $1 million mark," says Edwards. "Then we can start building the hospital."
For more information, visit the organization's Facebook causes page where Edwards will be posting video updates on his marathon training.