Striker John Carew has praised the impact of Aston Villa manager Gerard Houllier and believes he is getting closer to full fitness.[LNB] The Norway international produced his best performance of the season in the goalless Premier League encounter against Chelsea on Saturday.[LNB]The 31-year-old, Villa's top scorer in the previous three campaigns, is yet to get off the mark this term but he believes the whole team has benefited from the new training regime introduced by the former Liverpool boss.[LNB]Carew told the Express & Star: "We're working much more on the tactical side and that's good.[LNB]"We're doing more on possession play, on defensive organisation, offensive organisation. We are doing more of that and that's really good.[LNB]"I think that will show in results over the whole season, as we know more what to do and where to be.[LNB]"We work hard on new things and that's what we're all interested in, that's what we're here for, to make this club better and make the results better, to achieve goals and improve each season.[LNB]"If that means more work and harder work, which it probably does, then that's good."[LNB]The forward is also determined to play a 'bigger role' in the claret and blue jersey.[LNB]The Holte End favourite was called up by Houllier at the weekend after first-choice forward Emile Heskey was ruled out with a back problem.[LNB]Carew insists he is now fit and firing again after being hampered by recent knee trouble.[LNB]"I felt good. I had a good game with the national team and got some match fitness," he added.[LNB]"I'm feeling like my form and fitness is coming back so now I'm hoping to be a bigger part of the team again now.[LNB]"I just need to get my physical state back to 100 per cent again."