If your idea of exercise is getting up from the couch to fetch the remote, then you’ll cringe at the thought of the Land Rover G4 Challenge.

With off-road driving at its core, the exciting global adventure race, run in conjunction with the British Red Cross Society, tests competitors’ mental and physical abilities over 1550 miles and 600 hours (in just three weeks) in some of the harshest environments known to man.

After taking several wrong turns onto roads that don’t actually exist (thank you sat-nav), I arrive at Eastnor Castle in Herefordshire to watch the national selections. Here it’s the top two men and top two women who go through to international selections.

From there, only one man and one woman will represent Britain at the Challenge finals in Mongolia in June next year.

Upon arrival at the picturesque Malvern Hills estate I am immediately lured into a bright-orange Discovery 3 with the promise of a Mars Bar and Land Rover branded fleece. The Disco then conveys us to a water-logged quarry, where I meet up with Challenge hopeful Campbell Walsh.

There was only time for small talk as it’s his turn to do the timed slalom kayaking course. It’s no coincidence that Walsh posts the best time out of the 24 competitors, because the man recently bagged the slalom canoeing silver medal at the Beijing games.

After his stint in the ice-cold water he explains, “G4 is not just about physical fitness and endurance, it’s about dealing with situations and intuitive decision making”. At the time I wasn’t exactly sure what he meant, but it all made sense after I’d seen the nighttime orienteering exercise, which required some serious savvy.

I follow Campbell’s progress at the mountain biking and first aid tasks and feel he has a strong chance of making through to the International selections.

The first day is done and it’s time to retire to quarters, which happens to be a G4 tent. In it there’s a roll-up foam mattress, a sleeping bag and a very small pillow. It’s utterly freezing but good fun nonetheless.

Day two’s action is equally frenetic and Mr Walsh is still giving it his all in the orienteering, bridge building and zip line tasks. All the activities are done and it’s now results time. This is going to be close.

The names are announced. Gutted. Campbell doesn’t make it. It’s trainee doctor Andrew Grieve and 28-year old Bruce Duncan that move on to international selections, while adventure racers Sarah Davies and Mia Leijerstam finished as the top female contenders.

Good luck to them, I say. Now, where’s my remote control? Follow the rest of the action at www.landroverG4challenge.com