Whippet-lean, clear-skinned and full of energy, Gething looks like he’s never seen a potato chip in his life. He assures me this is not the case.

“Before I started on this I was 35kg overweight, I smoked and I drank too much.”

It’s very hard to imagine his chubby, unfit former self, but I’ll take his word for it. Gething says things came to a head in 2008, when his wife, Trilby, was two months away from giving birth to the couple’s first child.

“I told Trilby I’d given up smoking but she caught me outside having a cigarette with my neighbour. She sat me down and said, ‘Your daughter’s about to be born. You’ll be her role model. I love you but is this the person you really want to be for her?’”

Gething ditched the cigarettes and instead took up cycling and, later, running. To his surprise, he found fitness even more addictive than nicotine.

“I have a bit of an obsessive personality. I got hooked on losing more weight, running faster, cycling further.”

He soon discovered a community of fellow fanatics.

“One day I was overtaken by a trio of cyclists on Hiram’s Highway. They looked really buff and fit, not like me, but they invited me to ride with them. I couldn’t keep up that time but I kept coming back until eventually I could. We’ve been close friends ever since.”

As he became ever fitter and faster, Gething started compe­ting. His first running race was a civilised 8km. Gradually, he built up to marathons, triathlons and Ironman contests. He then heard about a global event – in the truest sense of the word – the World Marathon Challenge, and decided that next, he’d like to conquer the planet.

It wasn’t clear how he would find the time. A veterinary doctor, Gething runs the East Island Animal Hospital, in Shau Kei Wan, with Trilby. By this point, the couple, who met when they were at university together, in Perth, Australia, had two young daughters, two dogs, a cat and some fish. How did he squeeze a 20-hour training regime into his week?

“Weekdays I got up at 4am, trained for two hours, came home, got the kids ready for school, went to work, came home, played with the kids, and went to bed by 8pm. At the weekends, I did double training sessions. I lived like that for six months.”

That sounds dreadful. I’m feeling mystified again. Did he enjoy it?

“Not really. It wasn’t much fun and I had no social life. It was like groundhog day. Every day.”

Relentless, Gething’s book about his globe-trotting multi-marathon, has just been published. Blending running memoir with travelogue and sporting history, it’s a capti­vating study of the psychology of endurance and competi­tion, complete with battling egos, intense rivalry, outbursts of fury and deep introspection. Gething unravels and analyses his own moti­vations and emotions, and considers those of other runners, to track how changing moods and shifting relationships have an impact on success. I’m sur­prised by this. In my ignorance, I’d assumed that winning a marathon was a matter of putting one foot in front of the other, as quickly as possible. But apparently not.

“For any race longer than an hour, winning is at least 80 per cent psychological,” says Gething. “It’s usually not the fastest guy who wins. Confidence and razor-sharp focus are critical. It’s having the ability to accentuate your positives and minimise your negatives. If you get your mind in the wrong place, if you lose your nerve and you’re not happy, then you won’t win.”

What gives him his edge?

“Well I’m not the fittest or the fastest, and I haven’t done the most training, but I’m stupidly stubborn. I never give up. I’m also an optimist and when things get hard, I believe they will get better again.”

The first race began on January 17, in Antarctica, less than 1,000km from the South Pole, with the thermo­meter hovering around minus 20 degrees Celsius. Gething arrived with no idea of the danger of running in such cold conditions. The camp doctor’s pre-race briefing came as a shock.

“He said, ‘If you sweat, you’ll die.’” The doctor explained that sweat freezes instantly, forming a solid block of ice around the chest, which triggers rapid hypothermia. “At that point, there’s nothing they can do. As an ex-fat guy who usually runs in subtropical conditions, I’m a sweat machine. So this was worrying.”

The glacial breastplate never materialised, but the doctor stopped Gething at the final checkpoint, pulled off his woollen beanie and slammed it on the table. Shards of ice flew off.

“I’d been sweating into it and it had frozen solid. He said that had I carried on, my brain would have cooled to a dangerously low level.”

Fortunately, Gething was carrying a spare hat, but he couldn’t change his shoes.

“I’d chosen Gore-Tex trainers with a waterproof lining to keep out the snow. The problem was they kept in the sweat, which froze in the tips of the shoes.” When he removed the shoes, his two longest toes had turned black – a classic symptom of frostbite. “Eventually the ends of the toes fell off. Before that my kids had great fun sticking pins in them and because they were dead I couldn’t feel a thing.”

Gething won the Antarctica marathon by a significant margin, then flew to Chile. During the second marathon, the runners’ hierarchy was established. Gething was top dog but others were nipping at his heels. He writes that as the acknowledged leader, he had a psychological advantage, but it was essential to maintain his position – if the others smelled blood or sensed weakness, they would pounce. Perhaps Gething’s years as a vet have given him insight into the dog-eat-dog world of pack dynamics.

It was clear that his main rival was Australian ultra­runner Doug Wilson. Wilson is swift but has an Achilles heel – pressure. Seeing Gething behind him unnerved him and he would constantly check over his shoulder. Gething was often there. Wilson responded by bursting into a sprint, burning through his reserves and reducing his chances of main­tain­ing a decent pace. Gething – having assessed his com­petitors’ strengths and weaknesses – encour­aged Wilson to become the agent of his own undoing.

Tension between the two men reached boiling point during the third marathon, in Miami, in the United States. Mid-race, Wilson exploded with anger, and then pleaded with Gething to “just let me win this one ... for everyone at home”. Running side by side, the two men negotiated a truce – Wilson would triumph in this marathon and Gething would cross the finishing line first the next time.

According to Gething, stage races such as the World Marathon Challenge typically involve an “elaborate dance” between competitors. Behind the scenes, alliances are formed and deals are struck as participants devise colla­borative strategies to improve their own performances and chase down leaders.

On the negotiation with Wilson, he says, “It was better for everyone. The constant stress and aggression was becoming exhausting.”

The gift was also an investment, because it made Wilson indebted to him. How, I wonder, will Wilson feel when he reads Gething’s account of what happened between them?

­“I never want to hurt anybody with my writing. I spent a long time thinking about how to portray it with sensitivity while still being interesting and true. But there are bound to be events that I saw one way and he saw another.”

As agreed, Gething placed first in the fourth marathon, in Madrid, Spain. He then flew to Morocco for number five, and hit rock bottom. With the pressure and exhaustion mounting, and his drive draining away, he received an e-mail from Trilby with a photo of their youngest daughter, Madeleine, smiling proudly in her uniform on her first day at the Australian International School. Gething cracked, swamped by a wave of self-doubt and despair.

“There’s always a conflicting pull between work and family and hobbies, and seeing that picture made me feel incredibly guilty. I thought about the toll on my family, and how everyone had dropped everything to allow me to do this ridiculous race. It was such an important day for Madeleine and I wasn’t there.”

He decided to call it quits and head home but, following a timely intervention by another runner, he changed his mind. The race conditions, however, were terrible.

“It was dark, it was cold, it was raining, and we had to run around an industrial estate 11 times.” On the eighth lap, his right ankle landed in a pothole and twisted “with a sickening crunch”. Gething didn’t have time for an X-ray so he cannot be 100 per cent sure he broke it, but “I know a stress fracture when I see one, because I’ve dealt with so many in animals”.

He fought through the pain to complete the course, flew to the next marathon, in Dubai, and took stock of his injuries. Along with the blackened toes, his ankle had swollen to the size of a grapefruit, his Achilles tendons were creaking audibly, his knees were painful and his legs were so puffy that when he pressed on the skin, it didn’t spring back, leaving a thumb-sized crater.

It’s just as well he’s so stubborn. In Sydney, Gething’s hometown and the location of the final marathon, a combination of fierce determination and the support of Trilby, who had flown in to meet him, propelled him to the finishing line. There, he collapsed, and missed most of the jubilation surrounding his victory.

Now fully recovered (albeit with shorter toes), Gething hasn’t hung up his running shoes. Since his global epic, he has run a marathon in North Korea and competed in an Ironman race in Scotland that involved swimming across a jellyfish-infested sea loch (so cold it required two wetsuits) and scaling a couple of mountains. This year he survived Florida’s Ultraman race. Designed for those who think a standard Ironman is too easy, this comprises a 10km swim, 420km bike ride and 84km run.

“It was quite hard,” says Gething. Mid-life crises aren’t usually played out with such understatement.

With that our time is up and we say goodbye. Gething strides away and I head off down Sports Road in search of a taxi.

David Gething will be talking about Relentless at the Hong Kong International Literary Festival on Saturday. For details, go to www.festival.org.hk/program/
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