Economics and liberal studies teacher Chow Siu-fung says: 'It's hard for people to associate a petite female teacher with the marathon, and I wanted to show our girls that appearance doesn't matter.

'When I first started training, I found it hard just running 600 metres. Now I can run 42 kilometres,' she says.

Ying Wa teacher Fung Wing-yin also believes girls can achieve what boys can in long-distance running, which is why he, along with several other teachers, he established a school marathon club.

'Long-distance running requires endurance rather than power, so it's a sport suitable for both genders and almost any age. Girls are generally lighter than boys and this is an advantage,' he explains.

But, he adds, some tips are in order when training girls.

'You've got to get them interested and get as many involved as possible. Girls at this age like doing things together with their friends. Peer support is a great help.'

He adds that is important not to set training targets too high.

'Girls are generally less aggressive than boys,' he says.

'We can't push them too hard. Intensive, hard training from the start scares them off, so, we start with 3-kilometre runs in groups and extend the distance by 1 to 1.5 kilometres at a time.'

Seventeen-year-old twins Li Hoi-ping and Li Hoi-ting are new to long-distance running. But after several training sessions, they have built up their confidence.

'I wanted to try running long distance for a long time, but I was always afraid that I wouldn't be able to make it,' says Hoi-ting, who has discovered it is not as difficult as she expected.

'It's exhausting and it's discouraging when you're overtaken by other runners,' Hoi-ping admits, sweat dripping from her ponytail after a training session.

But she adds: 'I enjoy running together with my schoolmates and I like the feeling of making progress.'

Meanwhile, many of Hoi-ting's schoolmates joined the long-distance training to get fit - and ended up getting a lot more out of it than they expected.

'I find myself less tired during the day and more focused when I'm studying,' says Form Seven student Yeung Nga-man.

Now she realises that it is a sport that provides more than fitness.

'It gives you time and space to think and appreciate nature.'

More than 170 Ying Wa students will be among the 8,000 runners participating in the 10-kilometre race.

The Hong Kong Marathon will be held next Sunday.