True friendship is a sport of endurance, and Josh Duhamel is an all-time champ.

The actor, 50, has nurtured his long-term friendships thanks to the Buddy Games, a series of competitive playtime activities he and friends created during childhood. The games continued into adulthood, even as Duhamel and his chums became “grown-ups with real jobs and families.”

“It's really hard to make old friends in general, and so I think the older we get, the more we appreciate each other,” Duhamel says. “The games are just a fun, goofy way to sort of celebrate it, but it's really about the coming together every year.”

Duhamel gave Buddy Games the silver-screen treatment with the zany action-comedies “Buddy Games” and “Buddy Games: Spring Awakening.” Now, he's trading in archery bloodshed and Komodo dragon pits for human cornhole and inflatable soccer matches.

The CBS reality series “Buddy Games” (Thursdays, 9 EDT/PDT), follows six teams of longtime pals as they leverage their tightknit bonds in an eight-episode tournament of adult field day games, hosted by Duhamel, for a chance to win $200,000.

Duhamel talks with USA TODAY about his new reality show, co-parenting with ex Fergie and starting a family with wife Audra Mari (edited and condensed for clarity).

As someone who has competed in your fair share of Buddy Games, what was your experience being on the other side as a counselor to the groups vying for victory?

Josh Duhamel: It was really hard for me not to jump in there and compete, honestly. I really wanted to make sure that if I was going to host this thing, I didn't want to just stand back and observe from the sidelines. I wanted to get in there with them, and I was never going to ask them to do anything I wouldn't do myself. So I did this full-on test-dummy thing before each big event, to show them how each one of them worked. That’s maybe what separates this show, that I felt like a real part of the group.

Even though you didn’t formally compete, what was the hardest challenge for you?

We had to jump on these pink flamingos and paddle our way across this lake. Well, each of those teams had three or four players. We shot it in Bogota, Colombia, so we're up about 6,000 feet above sea level. I jumped in that water to paddle that flamingo over to the dock and then put on flippers and run down the dock, and then break this ice. And I tell you what, I was gassed. I haven't been that tired since I played football back in ‘91. I literally looked around to make sure somebody was watching in case I went under and started drowning.

Aside from the intense competition, some of the drama on the show arises from the alliances teams form with each other to get a leg up. How do the contestants’ relationships evolve over the course of the season?

It's like a big adult summer camp, and these grown adults are living in a big cabin together. So no matter how well you know your friends, you probably don't bunk up with them very often. But the teams that weren't used to spending a lot of time together really sort of felt it. And a lot of the drama comes from the infighting.

During a recent appearance promoting the show, you gave a shoutout to your son Axl Jack, who turned 10 last month. What’s it been like watching him grow up, and do you plan on introducing him to the Buddy Games as he gets older?

I don't think there's anything more rewarding in the world, at least for me, than to watch your kid grow up. You can't even explain the kind of love that you have for these kids until you have one yourself. All the phases he goes through, from superheroes to now loving soccer, every year he gets into different stuff. We've talked about me and my buddies who do the Buddy Games ― and all of them have kids now ― doing a father-son, father-daughter type Buddy Games, where they compete against the old guard. I'm not sure we would win at this point, ‘cause some of those guys have kids who are off to college now and kind of in their prime.

In other family news, you and your wife Audra shared Monday that you're expecting a baby. Congratulations! How does it feel to be expanding your family?

It feels amazing. I can't imagine doing it with anybody but her. She's going to be an incredible mother, I can't even tell you. She's made for this. She'll be a fun mom.

You co-parent Axl Jack with your former partner Fergie. How has that experience changed your outlook on teamwork and friendship?

It was really important both for she and I to make sure that we put aside (our) differences for his benefit. Fergie has been great. She and Audra get along really great. She's been really supportive of this next phase for both of us. She's a really good mom to Axl, and we just have a good working relationship as far as raising our son together. I'm actually really, really lucky because I've seen cases that aren't like that.

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