For some, it's a simple exercise. For others it can be mortifying, and Sam Kasiano apparently couldn't get anything out as he stood in silence in front of the group.
"That's 100 per cent more daunting than playing Australia," says Dean Whare, who blurted out a rendition of Maroon Five's Sunday Morning ahead of his debut against the Kangaroos last year.
"It's so scary getting up in front of the boys and showing off your talents. A few of the boys like getting up there and having a sing."
Whare doesn't seem to hold many fears, certainly not on a rugby league field, and looks entirely comfortable in international rugby league even though he's played only three tests.
The 23-year-old has nailed down the right centre spot and his consistency highlights the issues the Kiwis have at left centre.
He's now a critical component of a fairly potent right edge alongside Sonny Bill Williams, Shaun Johnson and Roger Tuivasa-Sheck.
Whare might not have made it to the World Cup if he hadn't left Manly at the end of 2012. He played 25 games for the Sea Eagles across three seasons as he served an apprenticeship under Steve Matai and Jamie Lyon but needed to move if he was to graduate to the next level.
He moved across town to Penrith, which was in the early stages of an ambitious five-year plan, and succeeded Michael Jennings who was a high-profile casualty of the changes under coach Ivan Cleary and boss Phil Gould. It was difficult at first but Whare became a critical element in a squad that came closer than most expected at securing a spot in the top eight.
"My main goal was to play more consistent and regular footy," he said. "At Manly I didn't get much game time over those three years so went to another club. I needed more game time to give me a chance of making the World Cup squad. I'm very happy with the move I made.
"I was there for three years and learned a lot off Jamie Lyon and Steve Matai. They took me under their wing and I couldn't have learned any more from them. But I thought it was time to move on and start my own career at a new club."
Whare has now scored 14 tries in 49 NRL games, including a hat-trick on debut in 2010, was named man of the match in the Kiwis' opening World Cup game against Samoa and is seen as one of the best young centres in the game.
He's on his first major tour - he previously ventured to the UK with Manly for the World Club Challenge but didn't play - but doesn't seem to get overawed by much.
"I love playing these big games," he says. "I played my third test against Samoa and each game I get more confident. Confidence is high at the moment and can't wait to get out there to do it again."
He gets his next chance on Saturday morning against a Papua New Guinea side who have already been eliminated from quarter-final contention. They threw away an opportunity to beat France in their opening game when they missed a penalty on fulltime in front of the posts and were then well beaten by Samoa 38-4.
Kiwis coach Stephen Kearney has opted for close to a full-strength lineup for the game - Simon Mannering, Frank Pritchard and Jared-Waerea-Hargreaves are being rested - in the hope of developing combinations.
The biggest questionmark is at left centre, where Bryson Goodwin gets another chance. He benefits from being the only left centre specialist - Krisnan Inu plays right edge - and Kearney would probably need to opt for a second-rower like Mannering or Alex Glenn if Goodwin doesn't convince against Papua New Guinea.
"I thought the first game for Bryson was a bit of a feeler and him getting used to the system and how we want to defend," Kearney said. "As a group, we improved our defence against France, and Bryson defended a lot better in that game. Giving him the opportunity alongside Manu Vatuvei and Kieran Foran this match, I think that'll help him to build that confidence."
