They have been through gruelling training similar to what the Combat Diving Course trainees undergo and had to meet the standards of actual naval divers before being allowed to act in the movie Ah Boys to Men 3.
Yet, when they were filming their new extreme sports reality show Ah Boys No Limit, actors Joshua Tan and Charlie Goh readily admitted that they were less gutsy than 16-year-olds.
Speaking to AsiaOne last week, Joshua, 30, said that they were filming an episode in the East Coast Park skate park and observed a lot of youngsters performing stunts that they were scared to try for the first time.
Charlie, 32, said: "There were a lot of kids there that day — parents brought their kids — and I tell you, these kids are just daredevils. You know as we get older, we get more and more scared? But kids generally just have no fear so you see the things they do are quite crazy.
"Then when you try to do something that is, like, half as dangerous, you also feel scared. And when everybody is looking at you, you get that pressure to want to do it. But then again, you need to consider your own safety as well."
It's not that they lacked the courage; they acknowledged that in the event of injury, they might not be able to act and that's where the bulk of their income comes from.
Joshua added: "The kids were skateboarding down the slopes and doing 360 [degree] flips in the air. It's insane! We can't do it. If we fall on our heads, that's it for us. We cannot work anymore."
In Ah Boys No Limits, which is out on mPlay (a new free-to-use, multi-region video streaming platform), the cast of the Ah Boys to Men film franchise reunite to compete in a series of extreme sports with the aim of defeating a 'big villain boss' in the final episode.
Some of the activities that will be featured on the show include BMX, parkour, archery, rock climbing, cable skiing, and Ninja Warrior.
Maxi suffered a hairline fracture
And the concern for their safety is justified, considering that Maxi Lim suffered a hairline fracture while filming the parkour episode.
The 33-year-old told AsiaOne in the interview: "You can't do parkour with pads, protection, shin guards, and stuff. So we have to do it the authentic way — bare-skinned. We were doing it on top of this rooftop carpark and an hour into the filming, I jumped and landed funny, and I [suffered] a hairline fracture on my foot."
However, Maxi admitted that he "didn't call for a cut" to the filming then and continued with his activity.
"But after every jump, I got weaker and weaker and it was harder and harder to jump, and harder and harder to walk. Then I realised I really messed something up."
Joshua, who was present at the filming, said it was "quite bad". He explained: "Parkour is quite a dangerous sport. It's probably one of the most dangerous sports in Ah Boys No Limits. He (Maxi) didn't really fall flat on his face but he banged his leg against concrete. That's pretty intense.
"Instantly, everyone just went quiet. Like the crew, like me and Aden (Tan) who were competing against him, we just went quiet. Everyone knows when something bad has happened so we just instantly went quiet then faster rushed over to see if he was okay. We were quite worried for him."
The actors — who have shared a very strong camaraderie and brotherhood since their Ah Boys movies — admitted to trash-talking each other during the filming of Ah Boys No Limits. But no one cracked any jokes at that moment because they knew it was serious.
However, that didn't stop Joshua from taking a dig at Maxi during the interview as he said that every time the latter is on set, he suffers massive 'burns' (slang for making a diss at someone).
"He's talking about injuries to the heart and to his ego," Charlie chimed in with a laugh.
In all seriousness though, Maxi is doing well, although he admitted to feeling some pain still if he does long-distance runs. This isn't even his worst injury though, he revealed, as he suffered a deep gash while filming Ah Boys to Men 3.
"There was a scene where I had to jump into the sea and I cut my hand on some barnacles or something on the side of this ship. There was a deep cut and some of the flesh was like floating in the water, so that was quite bad," Maxi recalled.
Ah Boys No Limits makes the cast more real
The idea for the show had been in the works for a long time, since the filming of the 2014 movie The Lion Men, and the Ah Boys jumped at the chance to reunite onscreen in a more organic setting that allow them to have fun.
When comparing the filming experience between the Ah Boys movies and the reality show, Charlie said: "On the Ah Boys set, we need to work, we need to act. But here, we don't have to. We just go and have fun and enjoy ourselves and just do what we do: talk nonsense all the time."
And the Ah Boys certainly enjoyed their time participating in sports that they don't usually do. Maxi found archery to be his favourite because he "got to be like (Lord of the Rings') Legolas" and added that it was not as simple as it seems due to the technique involved.
For Charlie and Joshua, it was Ninja Warrrior — although the former said that he wasn't invited but he would have loved to participate.
"That was my first episode and I kicked everyone's asses. I kicked them upside down. So Charlie, if you had joined, you would have presented a bit of a challenge to me," Joshua confidently declared while flexing his biceps.
Jokes aside, Charlie appreciated how much the show allowed him to test his limits.
"Sometimes you're scared of doing things, but it's taking that leap of faith, taking that step to get out of your comfort zone, then you'll realise what you can actually do," he said.
Joshua, who went up against some female contestants, learnt a lesson in humility.
He advised: "Never underestimate anyone, especially the ladies. You may think that all these challenges are physical, but no, there are really sneaky challenges and it's anyone's game. Sometimes I'm a bit over-confident because of my natural attributes but I've got to remind myself that it's not just about the physical [aspect]."
Maxi added: "We haven't shot something together for a really long time. We really enjoy the camaraderie and hopefully we can shoot Ah Boys to Men 5 soon and this can be like a warm-up to get everybody's chemistry going again."