A keen marathon runner is preparing to take on his biggest challenge by running the length of Great Britain for his best friend, who was seriously injured in a motorbike crash.

A keen marathon runner is preparing to take on his biggest challenge by running the length of Great Britain for his best friend, who was seriously injured in a motorbike crash.

Self-employed builder Matt Harrison from Attleborough is planning to run from John O' Groats to Land's End in the summer to raise funds for three life-saving good causes.

The 29-year-old's 873 mile challenge comes after his friend, Chris Taaffe, was left in a coma for several weeks following a motorcycle crash in south Norfolk on October 1.

It was thanks to the rapid response of the East Anglian Air Ambulance and the Addenbrooke's Critical Care Unit in Cambridge that saved the biker's life.

Mr Taaffe, 29, from Kenninghall, is now out of critical care and has begun to eat and speak under the treatment of the Colman Centre for Specialist Rehabilitation Services in Norwich.

Mr Harrison is now hoping to raise thousands of pounds for the three organisations by spending a month running 30 miles a day between John O' Groats to Land's End.

The former Banham Zoo keeper, who has completed two London Marathons and run the length of Hadrian's Wall from Newcastle to Carlisle last year, hopes to start his latest adventure in August. He added that the run would be 'long, tough and emotional'.

'Chris is progressing well and the money I raise will not make any difference to Chris, but will help people in the future. You never know when you'll need the air ambulance.'

'I love a challenge. I have spent a lot of time organising, but the training started two weeks ago. The hardest part is working for 12 hours a day and finding the strength and time to go running,' he said.

Mr Harrison can be sponsored at www.mattysbigrun.blogspot.com