Tindall takes part in major endurance event

Yorkshire-born Tindall, 36, is one of about 300 sports men and women taking part in the Artemis Great Kindrochit Quadrathlon by Loch Tay in Perthshire.

Challengers will take on a 1.35km swim, followed by a 24km run, an 11km kayak and a 54km cycle.

Tindall will be partnered by ex-Scottish international scrum half Rory Lawson and will compete against British skiing champions Chemmy Alcott and Dougie Crawford.

The gruelling event is expected to raise £250,000 for charities Mary’s Meals and Mercy Corps.

The quadrathlon, now in its 15th year, has previously been won by round-the-world cyclist Mark Beaumont who completed it in eight hours 37 minutes.

On reaching the finish line, each team must chop a watermelon in half with a sword.

Tindall, the husband of Zara Phillips, said last month: ‘’The biggest challenge for me is definitely the run. It’s over seven munros, so it could be an issue.

“Rory’s 20kg lighter than me and better at running. He’s not the best swimmer, so I said I’ll wait for him after the swim if he waits for me after the run.

“I think if we can do it in 12 to 13 hours then we’ll be over the moon.’’

The former Bath and Gloucester player, who was a member of the 2003 Rugby World Cup-winning squad, has been training for the event since appearing as a contestant in the Channel 4 show The Jump and Bear Grylls: Mission Survive, shown on ITV earlier this year.

He said: ‘’I don’t know if any of that has quite prepared me for the wilds of Scotland.

“We’ve been speaking to a few guys who’ve done it before - like (former Scotland rugby captain) Rob Wainwright - for advice.

“I’ve been doing stuff on the bike, a bit of cross-country and practising the distances for the swimming, but not outdoors in lakes or anything.

“We’ve done no kayaking, so that will be interesting.”