Losing weight for Stranger Things allows David Harbour to do simple things such as sprint across the street

David Harbour says getting into exercise "opened up a whole new world" to him.

The Stranger Things star found improving his fitness "felt like a rebirth" as he could do "simple little things" like running away from oncoming traffic.

The 47-year-old actor told People magazine: "It opened up a whole new world, [I'm] a lot more pliable and a lot more teachable, even in my mid-40s, than I ever imagined it could be. And it felt like a rebirth. It was really refreshing and really exciting to feel like after months of training like, Oh now I can just sprint across the street if a car comes. Just simple little things like that that were really exciting for me."

David - who dropped 80 pounds to play Sheriff Jim Hopper in the Netflix sci-fi series set in the 80s - over the past few years "developed a new relationship" with his body.

However, despite the transformation, The Hellboy star - who tied the knot with singer Lily Allen, 37, and is now step-father to her two daughters Ethel, 10, and Marnie, nine - loves his "big body" the same as his "lean athletic body" after training for eight months for the latest season of the Duffer Brothers-created show.

David said: "I love my big body as much as I love my lean athletic body. Something about being an actor is you are allowed to live in different skin and I like being a chameleon in that way. I much prefer to be more of a chameleon, and figure out how it feels to be in a different skin."

David admitted that his newfound passion was sometimes something he found "tiring".

He said: "When you're training for something, you get experts around, trainers and nutritionists, and that's really helpful, but also it gets tiring. I am an artistic, creative personality who, in general, doesn't love to be told what to do.

I like to forge my own path. And so it gets a little tiring when you have all these people sort of telling you what to do and so you kind of want to go off and just do your own thing."

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