Carson said that after discussions with the sports scientists at the club, the decision was made to emphasise work on his agility and improve his muscle mass.
"I feel as sharp as I have ever been and a lot quicker and more agile," he told the Daily Mirror.
"At Liverpool they have a more general system where everyone does the same weight training but here everyone has specific programmes.
"The Villa staff suggested getting my body fat down to get me sharper and I have been at that for a month now and feel really good.
"As a goalkeeper if you are not carrying as much weight and are quicker round the goal you are bound to make more saves that you wouldn't normally.
"I feel sharper in training and am just looking forward to the next few games because it is about trying to make the step up now to the England team.
"But I can only try and do my best for Aston villa and put performances in every week so when I get a chance I will be ready.
"I am just here for the season initially but hopefully if I do well there will be a chance of me staying, as when the contract was done with Liverpool it was a loan with a view to a permanent deal."