The 34-year-old underwent an operation on his hip after winning the Super Bowl with his old team, the Baltimore Ravens, and has missed all of his new side's pre-season as a result.
He told the club's official website: "I've been progressing. I feel strong, but I know I still have some things that are weak because you have that hip surgery; you lose strength, which you're usually losing your glut strength, your hamstring to overwork.
"My left hip was compensating as well. It's a lot of maintenance that I have to do to make sure nothing else happens and I pray nothing us happens, but you can't control it. That's football. You tend to have injuries."
Houston open their regular season against the San Diego Chargers on Monday.