The actress, who plays Eva Price in the ITV1 soap, was 15st as a teenager and wants to share tips on how she transformed to a 9st size 8-10.
She has described her daily workouts with close friend and personal trainer Sam Witter as "awesome", saying that he "butt kicks" her through gym sessions, the Daily Star Sunday reports.
"There's no doubt that Catherine looks the part these days. She is putting a tremendous amount of work into looking the way she is," a friend is quoted as saying.
"And she is excitedly telling people that she wants to produce a fitness DVD for Christmas. They have been huge earners for Corrie stars past and present. So Catherine is thinking, 'Why not do one myself?'
"Nowadays she is full of confidence and turns heads because of her figure. She has kept her bust but reduced other parts with carefully selected workouts in the gym and dieting."
Beverley Callard, Vicky Entwistle and Debbie Rush are among the Coronation Street stars to have previously released workout DVDs.