Chris Thrall set out to run an ultramarathon a day from John O'Groats to Land's End, solo, unsupported and sleeping in a tent by the side of the road. He'd not trained for two years, having been disabled whilst awaiting major spinal surgery. His backpack alone for the 999-mile slog Weighed over fifteen kilograms. Most said Chris couldn't do it. The former commando promised he would. Because to a Royal Marine success is simply a State of Mind ...