When a person (often fitness-athletes) uses photoshop to edit pictures of themselves, in order to look more muscular and lean. The term came from combining the word "gains" and Adobe Photoshop.

It was made popular after several Shredz-atlethes were exposed for editing their own photos before posting them, for example Paige Hathaway and Devin Zimmerman.
Person: Have you seen this guy called Devin? He's shredded!
Bradley Martyn: Nah man! It's just adobe gains!
by P_Explicit June 29, 2016
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