As one watches Mr Zermatt Neo chomp his way through a massive, 3.2kg bowl of tendon - tempura on Japanese rice - it is difficult to imagine that he grew up having digestive problems.

It is even harder to believe that the 29-year-old competitive eater is a personal trainer. He gamely shows off his biceps and six-pack after the tendon challenge - at Ramen Champion's new Don Meijin at Bugis+ on Feb 15- which he completed effortlessly in 20 minutes and 39 seconds.

And then, the bubbly Mr Neo asks: "What's for dinner?"

He gets laughter in response to what must surely be a joke, then says that he is "not kidding" and is only "70 per cent full".

He entered the world of competitive eating in November 2013 at Ramen Champion, when a gym buddy signed him up for a ramen-eating contest. With barely any training - just the knowledge that "I can eat" - he slurped up 11 bowls of ramen in under 20 minutes. He emerged the Singaporean Champion, finishing second to Japanese celebrity competitive eater Tomoko Miyake.

Three weeks later, he joined a pizza-eating competition and won that too, by finishing a 21-inch pizza in 16 minutes.

Since then, the 1.76m-tall eating machine, who weighs 65kg, has participated in more than 30 eating competitions. The bachelor says: "The crowd and adrenaline really get me going, plus, I love to compete. I didn't have a sport that I excelled at in school, so I guess it's pretty cool to say that this is a sport that I'm good at."

He is a member of Food League Singapore and was recently crowned the champion at the league's inaugural eating contest last month, after polishing off 92 chicken wings in eight minutes at Wing Zone in Buangkok.

Food League Singapore was formed last year by competitive eating enthusiasts to standardise eating contests and introduce a national ranking system.

The league organises more casual "challenges", such as the tendon challenge just for Mr Neo at Ramen Champion, as well as more formal competitions, which bring together other competitive eaters.

Save for his passion to eat and compete, Mr Neo is no glutton. He counts his calories and eats steamed food, such as chicken and salmon, along with plenty of vegetables, when not competing.

His habit of eating well started at the age of 24, when the former human resource executive took an interest in bodybuilding. He also has a degree in nutrition from the University of Wollongong in New South Wales, Australia.

"My digestive problems went away when I started eating right," he says, referring to how, when growing up, eating caused him to throw up. "It's all about discipline and it's good that my job allows for my love to eat."

What do your family and friends think of your love for eating competitions?

They were quite put-off at first, especially my parents, who are vegetarians. They thought my stomach would explode after wolfing down all the food. But once they saw that I could take care of myself physically, they were not worried any more. Now, my mum calls me after a contest to ask if I had won.

How do you prepare your body for a competition?

There is no specific way of preparing, but I go on a caloric deficit two days before and after a competition. I also do cardio workouts six days a week. I don't eat salads, nor do I go on a low-carbohydrate diet. And I can't live without eggs.

But there has to be some method to the eating madness during the competition? Eat the proteins first because when you are full, you won't want to eat them.

Drink warm water as it relaxes the oesophagus when you are eating. Cold water restricts it and makes it harder to eat.

Know your limits. I generally try not to eat more than 3kg of food. Any more, and it gets very painful.

What is the most you have eaten in a sitting?

I've eaten 100 bowls of Thai boat noodles, which is equivalent to about 5kg of noodles. I've also eaten 200 sticks of satay in under 20 minutes.

What would be your dream challenge?

A breakfast meal challenge with plenty of eggs and sausages.

What was the toughest challenge you had to stomach?

I had to eat 3.5kg of cake, which was filled with buttercream. It had about 12,500 calories. That was tough because I was supposed to eat 2.5kg at first. I don't know how another 1kg was added to it. I had intended to finish the 2.5kg cake in 20 minutes, but with the additional 1kg, I took more than 30 minutes and felt so sick after that.

What was your tastiest challenge?

I love steak, so my favourite challenge was to eat 1kg of ribeye at Big Bern's American Grill in Toa Payoh North last year. I ate the meat with four side dishes in eight minutes.

What challenges would you decline?

I have a low spice tolerance, so I don't think I can do a challenge for spicy food.

Do you have cheat days?

Yes, once a week. I go for a buffet and just eat all I can - non-competitively, of course.