As I prepared to talk to Giles Crown, a highly regarded solicitor with Lewis Silkin and endurance runner, I found memories of Allan Sillitoe’s The Loneliness of the Long Distance Runner bubbling away in my mind. Would Crown, I wondered, share an understanding of the clarity of thought, allied with intense physicality, that the story’s narrator, Smith, experiences as he runs, on and on, over vast distances?

“Running provides a perfect blend of a physical and mental challenge,” says Crown, who this year completed the London marathon. “When you’ve trained hard and find yourself running well in the middle of an event, absorbed in the moment, you experience an amazing feeling. It’s almost one of immortality. Certainly there’s an immense surge of euphoria.”

Crown, 38, has been an aficionado of endurance events for the past 20 years. After graduating from Cambridge in Law, he read an LLM at University College, London. Back then, rowing was his passion. “I would train for two or three hours every day,” he recalls, adding that even suffering a collapsed lung did not deter him for long. “I ended up rowing for Imperial College, London and enjoyed every minute of it. Since I started work I’ve constantly tried to find the time to keep fit. It’s a crucial part of my life, something that has to be right for a healthy work-life balance.”

Crown’s early years in the legal profession were spent as a barrister. He completed a pupillage at 2 Hare Court (now Blackstone Chambers) and then a third six at defamation set 1 Brick Court. “I was fortunate to be taken on and spent five very happy years at 1 Brick Court,” he says. “The work was always good fun and interesting.” Crown’s caseload included instructions on behalf of Bruce Grobbelaar in his famous libel action against The Sun.

However, he went on to develop a specialist expertise in advertising law and joined advertising agency TBWA as its in-house lawyer. After two years – during which he wrote Advertising Law and Regulation, a definitive tome that does what it says on the tin – Crown settled at Lewis Silkin, where he is currently deputy head of its Media, Brands and Technology Department.

Crown is one of the few lawyers to have worked as a barrister, in-house lawyer and solicitor, for in joining Lewis Silkin he had to re-qualify. Throughout his career, endurance events have never been far away. “I try to do one major event a year,” he says, “so I’ve completed various triathlon and, this year, the London marathon.” His motivation for the marathon arose from his father-in-law, who died of cancer. “He was an extraordinary man and ran 10 marathons between the ages of 60 and 73. I felt that I ought to be able do one as well and raised around £4,000 for Marie Curie Cancer Care.”

Crown says he “felt awful” during the marathon: “It was much harder than I had expected.” However, he got round in a respectable time of just over four and a half hours, largely thanks to a remarkable training regime that he devised. He lives in Ealing and, on the way to work, would alight on the Piccadilly Line progressively closer to Ealing: “It was great, running to work through Hyde Park, St James Park and along the Embankment, gradually increasing the distance I had to run. It was dead time otherwise and a brilliant way of building up my fitness.” He would also run along the River Thames near Ealing, or in Richmond Park, on weekends, and offers an explanation of the joy of running – especially to work or back – with which many lawyers will empathise.

“When I’m running I never listen to music or have any distractions. I leave my mobile and my Blackberry at home. I simply run and immerse myself in running. In today’s world, it’s just about the only time when I can’t be contacted.”

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