Only beer breaks will stop Buster in his tracks

Recent remarkable tales of triumph over adversity in the London Marathon have included former cancer patient Lloyd Scott, who competed in a deep-sea diver's uniform and, most movingly of all, former boxer Michael Watson, who overcame brain damage to complete the run in a week. Buster has made his own age-defying challenge all the tougher because for 90 years he has been a habitual drinker and smoker. And he won't clean up his act for the race. He intends to stop for a sip of his favourite bitter, which he drinks with a segment of orange, and a cigarette along the way.

"I've been smoking since I was seven," he said. "When I get to the line, if there isn't a pint of beer there waiting for me I'll want to know why. I'm not worried about the fags because I'll carry them with me. Everyone says smoking kills but it's taking a long time in my case. I don't change. If I do, I will make myself ill."

Buster is under the expert guidance of Harmander Singh, who trained his father, Fauja Singh, in the build-up to him becoming the oldest person to have run a marathon; a record he set in London when he was 93. There seems little chance that, even if he manages the 26 miles 385 yards, Buster will reach the finish line on The Mall before the street sweepers move in.

His trainers reckon it will take at least 12 hours. Buster attributes his remarkable vivacity in part to never having retired. He still helps out cleaning a fleet of vans at a firm around the corner from his flat on Lambeth Walk.

"If I wasn't working I would fold up and be in a wheelchair," he said.

But his boss, Charlie Mullins, appears concerned that Buster may struggle on Sunday, although the scheduled "beer stops" will surely not help his hydration, especially if it is a warm day.

He said: "Of course there is an element of risk. He is not going to do it in less than 11 hours, though we want to do it in one day rather than stopping overnight."

Mullins jokes that Buster is as likely to be slowed down by his fondness for a chat about his life. "Buster likes to talk," he said. "He's served in more wars than we've been in."