Duncan Buchanan in action during the St Cuthbert's Way ultra-race

Imagine running a marathon. Not so tough, eh?

Now imagine doing it in the middle of winter, carrying a pack over rough terrain in the mountains. A bit more impressive?

Now, imagine after 26.2 miles of slogging through snow, hail, gales and an endless sea of mud, carrying on without stopping for another full marathon.

Towards the end of this second marathon, after 47 miles to be exact, you reach a checkpoint – your first chance to refuel and treat any blisters or niggles. Five miles further on, your second marathon is completed and you sigh a weary sigh. But still you carry on.

By now night has fallen, so the next 16 hours will be tackled through the night across bleak featureless moorland in the teeth of the winter weather. As the new day slowly dawns and the weak January light returns your third non-stop marathon staggers to an end. But still the torture continues. You’ve now been running virtually non-stop for more than 24 hours, and you still have a full marathon to go.

At some forgotten point during the night, the act of covering the ground became so entrenched that to stop will take a conscious act of will. The metres and the miles now creep past at a painful shuffle. This fourth marathon will take you on to the bewildering rollercoaster of the Yorkshire Dales. What we’re talking about here is a non-stop 109-mile battle with the elements, through notoriously tough terrain, tackling the debilitating effects of exhaustion and continual navigational uncertainty. Impossible?

Not so, claim Borders-based ultra-distance runners Duncan Buchanan and Damon Rodwell. The duo are both members of the Border Search and Rescue Unit, and have taken on the huge challenge in a bid to raise much-needed funds for the team.

Damon Rodwell takes part in the St Cuthbert's Way race

The Spine Race starts at 6am on 9 January at the southern end of the Pennine Way in Derbyshire. Now in its fifth year, this winter’s event incorporates, for the first time, a special challenge specifically for mountain rescue volunteers.

This race-within-a-race will pit Duncan and Damon against 200 fellow masochists, about a dozen taken from the other mountain rescue organisations through whose territory the Pennine Way wends its bleak and wind-battered way as it follows the high backbone of England from the peak District to the Cheviots, ending a few miles north of the border in Kirk Yetholm.

Damon Rodwell said: “Over the past few years, Border Search and Rescue has been fairly heavily involved with The Spine Race.

“Runners completing the week-long 268-mile option end up running about 30 miles along the edge of our patch, and in 2013 and 2014 the race presented us with a couple of fairly challenging rescues, the first in a blizzard to evacuate three runners from one of the refuge huts up on the border ridge.

“I’ve got into the habit of running from my home in the foothills up onto the route to accompany the lead runners for a few miles, and have this year taken up the cudgel to run the full 109 miles of the Mountain Rescue Challenge.

“It’s 20 years since I did my serious ultra-distance running, whereas young Duncan – at 45, he’s three years younger and about 15 years more sprightly than me – has only discovered the delights of pushing beyond the marathon in the last couple of years.

“He’s as strong as an ox, and I have every confidence that he’ll last the distance and put in a very solid performance. As for myself, the engine still ticks over and the spirit remains keen, but the old bones seem to creak a bit more than they did 20 years ago.

“It’s going to be a bit of a voyage of discovery and it’s by no means guaranteed that I’ll make the finish.”

Duncan Buchanan tackles a swollen river

BSARU was involved in rescue efforts during the recent floods in Hawick, evacuating people from their homes as the River Teviot rose before eventually bursting its banks.

Coincidentally, Duncan Buchanan and Damon Rodwell recently ran a 38-mile race in the Lake District, and passed through Glenridding, the village that has been flooded three times in the space of just over two weeks.

Scotland’s 27 mountain rescue teams are funded by a combination of government grant, which covers about half the Border team’s annual running costs, and charitable donation. The team spends a lot of time in effort fundraising, and are a very visible presence at the various common ridings throughout the summer.

Mr Buchanan said: “I look after the team’s vehicles, and our specially equipped off-road ambulance is due for replacement. This is going to set us back somewhere in the region of £50,000, so fundraising has taken on a fresh significance this year.

“Damon and I are hoping to give the campaign a healthy boost, and have set up online donation pages. In the darkest hour before the dawn, I’m sure the thought of the sponsorship resting on our completion of the race will help to drive us on.”

The two runners can be sponsored via the Border Search and Rescue Unit website.