"I survived hypothermia and frostbite"

It's a bright day in Wallsend, Newcastle, but it wasn't that long since the man before me was going to sleep in -30C.

Dave Gullane looks down at his fingers tentatively. He can't open bottles at the moment, but he'll settle for that.

Just under a week ago he stared at them, riddled with frostbite, fingers swollen like fat sausages - and that was after being rescued.

"I knew it wasn't right that I was getting this cold. As soon as I stopped I got ill quite quickly."

Dave Gullane had served in Helmand Province, but by his own admission had never done anything like the Siberian Black Ice Race before.

The 379-mile 'marathon' runs across Lake Baikal: the world's oldest and deepest ice lake, described by the race organisers as "an eerily spooky covering of black tormented ice." Even the CEO says it's "longer than England, colder than vodka and harder than granite".

Competitors have to walk, ski or cycle (yes, cycle) across the terrifying expanse, dragging their gear behind them.

Dave signed up for the trek after being inspired by his daughter Emily, who had undergone 100 hours of surgery with a steely determination.

But on the second morning of the trek, he began vomiting blood. He carried on. By the end of the day he had both frostbite and hypothermia.

"When I started getting cold while walking, I knew something wasn't right. As soon as I stopped I called the race doctor. Once they knew what was wrong, they said I couldn't continue."

Fortunately, the frostbite did not go further than his fingers and the hypothermia was caught before it became fatal.

Back in Wallsend, I ask him if he would do it again. The answer is "no": he wants to go one step further.

"I want to compete in the Race to the North Pole. This was a way of me getting closer to that aim."