SINGAPORE - He loved taekwon-do so much that he quit his stable office job to coach others in the Korean martial art, taking a 50 per cent pay cut in the process.
But Lai Han Seng, 38, a taekwon-do instructor at JH Kim Bukit Timah taekwon-do academy at The Grandstand, a lifestyle hub formerly known as Turf City, hasn't looked back.
Mr Lai's switch from information technology - a job that included dealing with backend computer systems - meant he had to work longer hours.
He now works 50 to 60 hours a week, including on weekends. As an IT systems specialist, he had to put in only 44 hours a week, without working weekends.
However, Mr Lai said coaching is a "rewarding" experience, especially when his students perform well.
"I enjoy helping students to achieve their potential, especially when they lack confidence. I am happy when they pull through to perform well at gradings or competitions," he said.
It was not easy for him to make the switch, though - he had less take-home pay, and had to adjust his lifestyle to pursue his passion.
"I had to be more prudent when spending. Often, I did not go out at all," said Mr Lai. But he was fortunate as his then girlfriend, who is now his wife, was supportive of his move.
While his friends and family were less supportive, thinking that there were limited career prospects in his new line, they have since come around and are happy that he is doing something he loves.
The dedicated instructor picked up taekwon-do when he was 12, inspired by the many martial-arts films he had watched.
"Back then, most martial artists upheld justice and were portrayed as 'good' people, fighting against 'evil' people. Being a martial artist was noble," said Mr Lai.
He was inspired by his coaches, who shared with him the values of martial artists, such as helping others, having self-control and learning to focus.
Taekwon-do was also a good way to exercise and learn how to defend himself, as well as be more confident.
From 1999 to 2004, Mr Lai was on Singapore's national taekwon-do team.
He took part in many competitions, both locally and abroad, his first one overseas being the 2002 Hong Kong Asian Cities Championship. He won a silver medal in the featherweight category.
The National University of Singapore (NUS) graduate started his own IT company after graduating in 2001 with a computer science degree.
However, the business folded a year later. He then got a job in the IT sector while doing a part-time master's in computer science at NUS.
He joined the university's taekwon-do club and eventually got into coaching at the club, because he wanted to "impart good values to students" and help people with the martial art.