An image of Shayne's body before and after popped up on screen and Shane said: "That is three years of dunking biscuits on Corrie."
Host Lorraine Kelly asked how he did it and the actor replied: "So I joined a company called U.P fitness, not just myself but my partner Sophie as well.
"She cooks fresh food every single day as well, I've got a sweet tooth. But I've lost over three and a half stone and she's lost just a little over three stone."
Shayne left his role as Aidan Connor in Corrie in 2018.
In May 2018, Aidan took his own life as he had been suffering with depression.
His death left both Weatherfield residents and viewers devastated.
Since leaving the soap, Shayne was cast in a film called Stairs and is currently starring in the UK tour of Band Of Gold alongside fellow former Corrie star Sacha Parkinson, ex-Emmerdale star Gaynor Faye, former EastEnders actress Laurie Brett and Hollyoaks star Kieron Richardson.
Will you be going to see Band Of Gold?
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