Matthew McConaughey has shared an unexpected bedroom secret that he claims greatly improved his relationship.

The 55-year-old Interstellar star, who has been happily married to Camila Alves McConaughey for over a decade since their 2012 wedding, offered a piece of advice to other couples on one simple change they could make to enhance their marriage.

Surprisingly, it's not couples therapy, top-notch communication, or even adding excitement to the bedroom. Instead, as McConaughey explained to Fox News Digital, the secret lies in swapping out a king-sized bed for a smaller, cozier one.

"I wake up one morning … and I realize Camila feels like she's a football field away," he recounted.

"Then, when it's bedtime, you want to cuddle up, but it's like, ‘Well, we’ve got to bridge this huge gap. Come about 12 feet, and I'll meet you halfway’."

Interstellar star Matthew McConaughey has shared some bedroom advice that'll apparently do wonders for your relationship (George Pimentel/WireImage)

The Dazed and Confused actor continued: "You're like, man, this king-size bed is not doing any favors for the marriage. Get rid of that thing."

McConaughey mentioned that he and his wife eventually settled on a queen-size bed, where they now sleep 'shoulder to shoulder'.

"I'm telling you," he asserted, "it's beneficial for your marriage."

The relationship advice doesn't end there, as the Hollywood star also emphasized the importance of maintaining a romantic connection with a partner, even amidst daily routines and parenting responsibilities.

"You've got kids, so you're often busy being a good mother and father, but you also have to ensure—and I could improve on this—that you say, 'No, this is our time,' " McConaughey advised.

McConaughey and Camila got married in 2012 and share three children together (Instagram/@camilamcconaughey)

He added: "You can't devote 100% of your time to just being a parent.

"One of the best examples you can give your kids on how to treat someone they might fall in love with is by showing them how you treat their mother and how she treats their father."

McConaughey and his wife Camila have three children together - Levi, 17, Vida, 15, and their youngest, 12-year-old Livingston.

"The only thing I ever knew I wanted to be was a father," he told PEOPLE in October 2020. "And it remains the pinnacle for me. Being a dad was always my only dream ... I can't think of anything more important."