Carefree, loud 20-somethings blasting music in the gym first thing in the morning can send a person one of two ways – out the door or up the NRL ladder.

For Api Koroisau it’s the latter, having played seven seasons of first grade for three clubs but never really enjoying the privilege as much as he does at Penrith now.

The energy of the young and spirited Panthers is infectious – they’re afraid of nothing and are bold enough to believe they can achieve anything.

In the past, Koroisau has been weighed down by the pressure of being a starting NRL hooker but this year he has been reminded of why he wants to be one in the first place.

Before Penrith’s preliminary final clash with South Sydney on Saturday night, that mindset is stronger than ever.

“I got caught in the trap too much of trying to play good footy in the past, knowing I had to do a job and knowing I was a starting hooker,” he told AAP.

“I got worried too much about the football side and less about the fun.

“But coming to a club like this, these young guys are never serious until they cross that white line so it’s just a bunch of fun being around here.

“It’s 8am in the morning and they’re screaming and carrying on with music pumping.

“You have to get up to that level, they give you no choice.”

And it’s translated into one of Koroisau’s best seasons on the paddock.

“I’ve been able to focus on having fun and that’s correlated to playing good footy. The more fun I have, the better footy I play,” he said.

His impact on the Panthers has helped ignite their attack, which was heavily doubted prior to the start of the season.

But now, on a 15-game winning streak, Koroisau believes the secret has been knowing when to have fun and when to switch on.

It’s a balance he said comes from a team that will do anything to win.

“I’ve been to a lot of clubs where they’ve been very professional, a lot of guys who are at the top of their jobs and displayed that all the time, whereas at a club like this no one is actually that serious until we enter a meeting or get on the footy field,” he said.

“The key is flicking the switch.

“It’s balance, we’ve got to turn it on and off.

“Right now these guys have the perfect balance.

“Everyone actually loves to play footy here so they want to win.”