The quirky event, set in Gawthorpe, near Wakefield, on Easter Monday each year, is one of a series of challenges Jason has set himself in the past year, to help him lose weight and raise money for the worthwhile Leeds-based charity run by Sue Ryder Care.

Jason, 38, who is a development manager for Gala Coral Group, said: "Last Christmas I was 16 stone and I decided to get fit and do something about it.

"My company pledged to raise £1million for the Sue Ryder charity and so I decided I would get fit and do good at the same time.

"I've lost three stone and I feel a lot healthier than I did this time last year," said Jason who is married to Clare and has two children Haydn, 10 and Megan eight.

Over the course of this year and next Jason will have taken part in 10 events, including the 10km Leeds run, Cross The Bay half marathon, and the 5km Roundhay Fun Run this year, and ending with the Great North Run in September 2010.

He has wanted to enter the World Coal Championships for years, after growing up in Gawthorpe and watching the event as a child. He is in serious training, running with 25 kilo weights in a heavy scaffolding sack to recreate the conditions.

The annual event, now in its 36th year, requires participants to carry a 50 kilo sack of coal along a 1100 metre uphill course, from the Royal Oak Public House, in Gawthorpe, finishing at The Maypole on the village green.

Jason has so far raised nearly £700 for Wheatfields Hospice which supports people with specialist palliative, end of life and long-term neurological care needs.

Anyone can sponsor Jason at his Just Giving page at: www.justgiving.com/ jasonwilliamson