The 21-year-old joined Villa from Leeds United in 2009, but injuries have limited him to just 41 appearances for the Midlands outfit.
"I feel good and I feel stronger than I have in the past. I started the season then ended up out of the team but I've been working hard and managed to get back in," he told the Birmingham Evening Post.
"I'm pleased with that but I want to push on, do better and have a lot more of an impact than I have done. I had a good run last year but I wasn't fully fit. I am now and it is nice. People judge you when you get a run of games in the team and it is nice to be judged when you are fully fit."
Delph cost Villa £8m from Leeds.