There's a hill behind Matt Millen's home in Bucks County that he used to climb. When his heart grew too weak, it became the "hill that crushed me."
Now, with a new heart, Millen believes he could get up that hill if he had to. So he's training again, kind of like he did during his football career.
"You know what the weird thing is?" Millen asked. "I've got to train this heart for me. I'm doing stuff and I think, 'I don't know how hard I should push it.' I'm not getting ready for a season anymore, not getting ready to bench 500 pounds anymore, but I still have the same mindset.