MONSTER. That is what her compatriots call her. You would never have guessed it, though, if you met 15-year-old Lee Sunae in person.

With beady eyes curtained by straight black bangs, a tiny mouth that offers many smiles but few words and a 1.62m-tall, 48kg frame that is built more like Barbie than beast, the South Korean teen looks anything but monstrous.

But the meek girl earns her reputation for her mightiness on the athletics track.

Daegu native Sunae, the youngest in Korea's 115-member national Open team, runs the century sprint in 11.74 seconds. That is as fast as the quickest female youth sprinters from the US, a sprints powerhouse. Singapore's national record is 12.12sec.

She is the favourite to win today's Asian Youth Games 100m final at Bishan Stadium, after emerging as the fastest qualifier (12.00) in Tuesday's heats, ahead of Japan's Akane Kimura (12.14).

'I'm aiming for the gold in 11.9 seconds,' said Sunae through an interpreter at the Games Village at Swissotel on Thursday.

'I'm not nervous, though there is a little pressure from the Japanese.'

The Korean media call her the nation's next sprint queen. AYG head coach Lee Jongwoo says Sunae is already his country's best.

In two years, he expects her to clock 11.3 and break Lee Young Sook's 1994 national record of 11.49, the same year Sunae was born.

Though not muscle-packed like most top sprinters, her flexible body is able to generate very powerful starts, said Lee. 'Mentally,' he added, 'she's also very strong.'

The only daughter and the younger of two children of a car salesman, 44, and housewife, 43, Sunae did her first 100m sprint at a school meet when she was nine.

By age 12, she was clocking 12.74. (Singapore's Schools National record for that age is 13.12).

Last month, at the Korean National Championships, she ran 11.88 to finish second behind 23-year-old Kim Ha Na (11.71).

Fuelled by the dream of winning a medal in front of a home crowd at the 2011 IAAF World Championships in Daegu, Sunae trains three hours every day in school under coach Park Hyuk Chan. She rests only on Sundays. During the holidays, she trains twice as hard.

'The boys are ashamed to race her because she's faster than them,' quipped Lee.

In fact, her personal-best time would have ranked her a decent 15th among 24 athletes in the AYG 100m boys' heats, which was won by Japan's Masaki Nashimoto (10.89) ahead of Singapore's Shahrir Anuar (11.07). The boys' final will also take place today.

In her free time, Sunae plays table tennis and listens to classical music and English oldies.

Does being called monster bug her? 'They mean that I run faster than others,' she said with a grin, 'so it's not a bad thing.'

JEANETTE WANG