By day their core strengths are crunching numbers and balancing the books.

But in their spare time a team from Huddersfield accountants Sheards are set to use their true core strength to tackle a military assault course.

They will take on a Tough Mudder challenge in Cheshire on Saturday, September 13 in aid of the Forget Me Not Children’s Hospice and Help For Heroes.

Tough Mudder is an extreme assault course featuring 25 obstacles.

Not only do competitors have to run 12 miles, wading and crawling through muddy water and tunnels, they must also tackle a host of intimidating obstacles, including ice pools, a 15 foot drop, 12 foot high walls and even electrified wires.

The team from Sheards includes, Tim Musgrove, Matthew Schofield, Joel Harrison, Andy Bell, Mark Stewart along with Dave Durrance, who should be fairly tough due to his membership of Huddersfield Rams Australian Rules Football team.

Tim, a tax and payroll manager by day, said he had signed up for the company’s annual fundraiser, without any questions and had a bit of shock when he found out more.

“I didn’t know what was until I signed up,” he said.

“It’s a brutal challenge, it’s quite extreme, but for a charity it needs to be quite a big challenge.

“I don’t think you can ever by ready for some of the obstacles like the ice baths or the tunnels.

“We’ll just have to see how things go on the day.”

The six-strong team have to complete the challenge together and help drag each other over the walls and through the bogs.

They are hoping to finish in under four hours and are looking forward to the beer that Tough Mudder rewards each competitor with at the finish line.

Tim added: “The only problem is you have to run through electrified wires to get to the finish line.

“It’s like a mirage, you’ll be able to see the beers, before you do it.”

The accountants are hoping to raise £1,000 for the charities.