When he is dead tired in the middle of his marathon run, one thought that keeps him going is another marathon of sorts.
Mr Mohanadas Kandiah, 53, says with a straight face: "I call it a makan-athon where I just eat all the food I see."
The thought of having a feast right after each marathon motivates him so much that he is driven towards the finish line.
Mr Mohanadas says sheepishly: "I go straight for the local dishes. I eat a lot of rice, some curry and just pile on the dishes at Samy's Curry at Dempsey Road.
Dressed in a loose T-shirt and pants, it's not immediately clear how fit he is.
But after the stockbroker shows this reporter some photos of him during his races, it's clear that 18 years of running has been beneficial, going by his toned physique.
Mr Mohanadas has endured hours of air travel to put himself through another punishing run in another country.
Most of these runs are the standard 42km, which he takes about four hours to complete.
And suffice it to say, he has spent a lot of time on the road and has seen a lot over the years.
Seeing someone pee by the side of the road might warrant an entry on citizen journalism website Stomp.
But he says that this is common during marathons. "When you have to go, you have to go," Mr Mohanadas says unapologetically.
Indeed, he hardly bats an eyelid when he spots a bared butt on the roadside now.
He adds: "Of course, there are portable toilets, but the queue is too long to hold it in very often.
"Besides, it's easy for the men as it doesn't require much effort for us to do it at the sidelines."
For the women, it's another story, he says. "That is why I encourage men to let women use the toilets first."
But when the going gets tough, the women have no choice but to get going - in the bushes.
"I have seen women scurry off to a bush nearby before they quickly pull off their tights to relieve themselves," Mr Mohanadas recounts with a laugh.
Deciding whether to hold your pee in is not the only concern during races - bloody nipples, calluses and blisters are also commonplace.
He says with a grimace: "As the jersey is rubbing against the nipples for at least three hours, they are bound to get sore and will bleed." Mr Mohanadas has experienced it twice before and says that "it's not a pretty sight".
He therefore swears on anti-chafe balm Bodyglide to prevent such discomforts.
"Better to apply Bodyglide to the inner thighs as it is another hotspot for chafing," he reveals.
But other people have a better method, it seems.
"I saw a Japanese guy cut two holes in his jersey for his nipples to combat the problem," Mr Mohanadas recounts.
The single man, who sports a bald head and tattoos, tells The New Paper on Sunday that he runs "just for fun" and doesn't care about his timings.
He loves marathons because he gets to meet and share laughs with people who love running.
"I once went up to a Hong Kong runner who had a piece of paper pasted on his back which said, 'Hi Sarah, Please marry me.'
"Of course, being the clown that I am, I went up to him and introduced myself as Sarah and told him I'd marry him," recalls Mr Mohanadas.
Besides carrying a camera to his runs, he always brings a whistle - to motivate people when they look like they are about to give up.
"Whenever runners - especially the first-timers - show signs of giving up, I'll blow the whistle and egg them on.
"Most of them are very appreciative, but there were some isolated incidents where they cursed at me when I encouraged them," he adds.
The self-proclaimed "sucker for races" admits that experience does not mean one will be any less exhausted. There have been times when his body didn't hold out and he couldn't continue the race.
Success in marathons didn't always come easy for Mr Mohanadas. It took three attempts before he completed his first marathon here in 1995.
And how did he feel after finally crossing the finishing line? "Shiokalingam".
Now, 18 years later, it's still "Shiokalingam".
But when this reporter brought up the recent Boston Marathon bombings, the avid runner turns sombre and says: "It's such a shock."
"But this will never deter me from continuing to compete in international races. In fact, I am more encouraged to show support in the only way I know how," adds Mr Mohanadas.
"To keep running."
"When I saw cars from the event, I just hopped on. But the 20-minute ride from Mandai to MacRitchie was extremely demoralising," he says.
Secrets of the trade
1. Always tuck money in your tights - you never know how the water support is during each race. The money will come in useful if you die die need to buy some liquids instead of queueing forever.
2. Cut your toenails before each run. Some runners have been known to lose them after marathons. An improperly trimmed toenail can catch part of a sock or push against the front of running shoes and prompt blisters and bruises. Sometimes, the toe appears blackened and can fall off.
3. Never wear new clothes on a marathon day. It will only cause more chafing. You don't want people to see bloodstains on your shirt.
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