"I had a moment when I was in Atlanta. It was the day before we started shooting and I was at the gym at the top of the condo complex, overlooking the city.
I was working out and this song, "Impossible," [came on]. I was doing this really hard workout — I was doing these step-ups and these squats, these stiff-legged dead lifts and I was looking out and that song was playing. And I got so emotional, because I thought, just a year before, I was so weak I could barely walk up, not a steep flight of stairs, but a very low graduated set of stairs, like three steps.
I remember just standing there and doing this extremely hard workout looking out over the city and thinking and the song's playing and I thought I used to think it was impossible like I could not do this."