Mike, 47, and Rebecca, 20, were hopping into the saddle to begin a 1,400-mile ride from John O'Groats to Lands End, almost exactly five years after Jane completed the same incredible journey while suffering from terminal cancer.

The pair left their Rothwell home yesterday to make the long trek north for today's start.

Both said they were looking forward to it – but admitted they were woefully underprepared for the event.

Mike, an IT expert, said: "I just haven't had any time to train. I think I've done about 30 miles. But that won't be much help as the first day alone is 50 miles and that's supposed to be an easy start!

"It just got too late in the day to start. I know that my backside is going to be really painful, so I thought why hurt it before I set off?

"One of the women on the support crew said she would be looking out for my behind. It's been a long time since someone's said that to me, and you've got to take compliments where you can get them.

"Seriously, apparently after about eight or nine days you get through the pain barrier – your backside gets broken in if you like. I just have to get that far first.

"It should be fun, though. Becca and I are really looking forward to following in Jane's footsteps, or rather cycle tracks."

Mike and student Rebecca are hoping the sponsorship raised from the End to End Challenge will help to smash Jane's ambitious £2m fundraising target.

Before she died last September, the mum-of-three notched up £1.75m and Mike and children, Suzanne, Rebecca and Steven want to complete her legacy.

They already organise the hugely successful Jane Tomlinson Leeds 10k which took place for the second time in June and attracted more than 12,000 runners.

The 21-day End to End event will take the cycling duo through Inverness, Edinburgh, Carlisle, Yorkshire, the Midlands, London, Wells, Launceston and Newquay before finishing at the most southerly point of the country.

They will be joined by friends along the way, including communications boss Ryan Bowd who also cycled across America with Jane and Leeds 10k race organiser Graeme Hodgson.

On five days of the route – including Settle to Leeds on July 21 – up to 100 members of the public are also invited to join the party.

Mike said: "We want it to be a really fun event and we'd love people to come out on their bikes and join us."

To donate to the Jane's Appeal End to End Challenge visit: www.justgiving.com/ janesappealend2endcyclingchallenge

* For more details of the Ride-for-All days log on to: www.janesappeal.com