Sebastian Stan’s slimming down was insufferable.

Stan portrays Motley Crue drummer Tommy Lee in Hulu’s new series “Pam & Tommy”. Stan, 39, lost a ton of weight for the role, something that was far more difficult than his experiences bulking up to play Bucky Barnes in The Marvel Cinematic Universe.

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“I was trying to lose weight and I still felt I didn’t lose enough weight,” Stan told Entertainment Weekly. “And people were telling me I was crazy and going, ‘You have body dysmorphia now’ — which I always did anyway.”

“I was just running and trying to get 20,000 steps a day, and then I was fasting for 16 to 18 hours a day,” he said. “And that definitely does something, especially if you’re [driving] in traffic. But I’m proud of the whole thing.”

The difficult weight cut was a necessary evil as far as Stan is concerned.

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“The physical transformation is a very important part to the acting process, and whether it’s him or a fictional character, I look for those things because I get tired of myself,” Stan said. “I do! I don’t want to do the same thing over and over again.”

“I know my Sebastian-isms and the things that I do so I like to be challenged. And the physical aspect of it, whether it’s losing weight or gaining weight or changing hair colour, it shifts perspective.”