Justin Theroux talks handling situations that aren't working following split from Jennifer Aniston

Justin Theroux says there's something to be learned from every experience that doesn't quite work out.

Theroux covers Men's Health July/August issue, showing off his fit physique at 46, and opening up about his success as both a writer and actor. The Spy Who Dumped Me star admits to not always being confident, but says he uses it to his advantage.

“I think doubt is a good thing,” he says. “We’re all doubting whenever we set out to do anything new. But that’s a motivating factor to try to make it good. It’s destructive if you let it creep over the entire process, but I don’t dwell."

"I doubt things, but I hope things, too," he continues. "That’s when you give it the best chance of success by working harder or practicing or rewriting. That’s how I deal with doubt. .... Or I just pretend I’m not doubting myself.”

Justin Theroux in 'Men's Health'
Men's Health

Theroux also opens up about how he deals with situations that have gone bad.

“I get up and do what I do,” he says. “When I do things I don’t necessarily want to do, or I get stuck in a situation where I’m like, ‘Oh, this was not the best choice,’ I’m still aware there’s something to be gleaned from that experience. You have to just find some nugget that makes it worthwhile. Otherwise you’ll completely give up. Bad work experiences are instructive: (A) what I shouldn’t do again; (B) how things are done wrong and how I can do better.”

As for what's next for him, Theroux is definitely spontaneous.

“In ideal circumstances, the bucket list just starts to happen if you’re leading your life well," he notes. "I happened to be driving past a skydiving school once and decided to go skydiving. It wasn’t anything I had planned. I always wanted to ride a motorcycle across Europe. I’ve done that three times now. There’s nothing I’m dying to do. Nothing gnawing at me. There are things I know I will do. I just don’t know what they are yet.”

The same spontaneity extends to his tattoos. Last month, he showed off his massive back tattoo dedicated to his deceased dogs.

“I don’t put a lot of thought into mine," he admits of his ink. "There are a lot of people designing their own tattoos who are frustrating a lot of tattoo artists. I’m real easy. I’ll go in like, ‘What should we do?’ ‘I dunno, what do you wanna do?’ So it’s kind of when the mood strikes.”

As for his incredible physique, Theroux credits it to hitting the gym five days a week, his primary workout being boxing.

<div>Men's Health</div>
Men's Health

"People get pissed, get emotional, and that’s kind of the point of sparring: Keep breathing, remain loose, not tense," he says.

<div>Men's Health</div>
Men's Health

Last month, Theroux was photographed in the south of France with actress Laura Harrier after splitting from Jennifer Aniston in February. However, a source told ET that the actor is definitely single.

“Justin is not in a relationship,” the source said. “He’s super social and loves meeting new people and collaborating on ideas with friends. These days he’s been spending time with friends and family -- he’s super close with his brother."


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