Updated

By Simon Evans

MIAMI (Reuters) - The Minnesota Vikings know to expect a deafening atmosphere when they take on the New Orleans Saints in the NFC Championship game at the Louisiana Superdome on Sunday, but insist they will be able to cope.

Returning to practice on Wednesday, the Vikings players trained with ear plugs and in front of speakers blasting out a loud simulation of the noise the 72,000 New Orleans fans could make.

Such is the volume inside the roofed Superdome that instructions from coach to quarterback and between the quarterback and his line are almost impossible in a traditional manner.

Childress recalled that during his time as quarterbacks coach with Philadelphia, the Eagles featured in an NFC Championship game in 2002 at the Edward Jones Dome in St. Louis where there was also incredible noise.

"Communication; that's the significant part of the challenge. None of those 70,000 people will come on the field and have anything to do with the win or the loss. It's like the Coliseum. It will be the people in-between the lines," he said.

BIG FACTOR

Vikings quarterback Brett Favre has no doubt that the atmosphere will be a big factor in the game.

"These games, they're tough anyway, but they're really tough on the road, because of the noise. Not only are you playing the Saints, but you're playing the fans, and all of those things work against you," said the 40-year-old.

"I'll emphasize that during the week. We'll practice as much like a game as possible with those elements, but there's no substitute for the game itself," he said.

Running back Adrian Peterson said the Superdome has the highest volume of noise of any stadium he has experienced.

"Playing there (last year) it was definitely the loudest stadium I've played in," he said. "So it's going to be very crucial for us to be sound with our protections and communicating out there."

The Superdome has never hosted the Saints in an NFC Championship game and the home team's quarterback Drew Brees says the volume has been rising week by week.

"It seems like every week this year as we won one and then one more the atmosphere got crazier and crazier, and I would expect nothing less on Sunday," he said.

(Reporting by Simon Evans in Miami; Editing by Nick Mulvenney)