At a recent interview, Ms Qin Yunquan described her teenage self as someone who lacked self-confidence.
But the now 27-year-old is no longer the same insecure girl.
In fact, the self-defence instructor has just been named one of the winners of the Queen's Young Leaders Award 2017 for her work in teaching martial arts to women and children so that they can protect themselves.
Her story kicked off a new video series, Heroes Among Us, produced by The Straits Times.
The eight-part series tells the stories of ordinary Singaporeans who overcame personal struggles to achieve greater things.
In the first episode, launched yesterday, Ms Qin spoke candidly about her past struggles.
Up until junior college, she was the only girl in her school's trim- and-fit club.
"I felt like a social outcast and decided to lose weight drastically," she told The Straits Times during the video shoot.
She started to exercise vigorously and ate only one meal a day. Her wake-up call came when her doctor told her in 2007 that she was going to die if she lost another 2kg.
She stopped her weight loss regime and picked up Kapap, a form of martial arts developed by the Israeli military.
In 2013, she took over the reins of Kapap Academy Singapore from her master, Mr Teo Yew Chye.
The academy not only teaches Kapap, but also provides free self- defence classes for women, children and elderly people.
"(We) teach our students to train and respond like a bodyguard... to overcome fear," Ms Qin said in the video.
Future episodes of Heroes Among Us will include the stories of former national gymnast Eileen Chai, whose sporting career was cut short by injury, and former prostitute Sherry Sherqueshaa, who is now an activist fighting for the rights of sex workers.
Heroes Among Us is one of five programmes helmed by ST in a recently announced partnership between Singapore Press Holdings (SPH) and the Info-communications Media Development Authority.
For more on ST's new programmes, go to http://www.straitstimes.com/videos