Five of the school's top athletes - Bosco Chan Heung-wai, Raymond Leung Cheuk-wing, Martin Mar Ting-pong, Andy Lai Ka-wing, and Peter Wong Kam-shing - have been hitting the school's gym…and the stairs.
The reason? They are training for their debut at the Race to ICC 100: SHKP Vertical Run for the Chest 2013.
Hong Kong is the seventh stop and grand finale of the international Vertical World Circuit. Other destinations have included the Empire State Building in New York, the China World Trade Centre in Beijing and the Landmark in Vietnam.
Athletes will tackle 82 floors, or 2,120 steps, at the International Commerce Centre this Sunday, as they embrace "vertical running".
"We were introduced to the sport by our PE teacher Mr Ho," says Martin, the school's swimming captain.
"All of us do different sports, but this kind of competition is attractive to all of us."
The group might be seasoned athletes, but they can't just show up on the day and compete without proper training.
On race day, every athlete has to run up a vertical distance of 484 metres. Of the seven vertical running competitions in the series, this is the hardest.
The five students started training a few weeks back.
On Mondays, Wednesdays and Fridays, they blast up and down the stairs after school to get some vertical running experience. On Tuesdays and Thursdays, they do muscle-strengthening exercises in the gym.
But the students felt utterly defeated when they first tried the sport. "After the first training session, we all laid down on the floor. We could not walk for 30 minutes!" Andy jokes. "We just sat there and chatted until we could walk again.
"The next day, we were all like disabled people, crawling step by step to our classroom."
Since then, they have built up their strength and learned tricks to overcome the challenges of the race.
"When people normally walk up the stairs, they often go for two to three steps at once," Martin says. "But we found that is a no-no for vertical running."
Their PE teacher Ho Hoi-to is a dedicated stairs-runner and has taken part in several races.
"Stairs-running is different to a marathon. If you go too hard at the beginning, you will get cramps and won't be able to finish the race," he says. "You won't even be able to walk."
It is vital to keep a constant pace throughout the race. That is harder than it sounds, as contestants will be running on their own once the starting whistle blows.
Ho has one last trick to teach his students this week: to use their hands. Students, he says, should use the handrails to reduce the burden on their legs.
Associate professor at Baptist University's department of physical education, Dr Lobo Louie, is the race adviser. He says the sport is perfect for Hong Kong because the city has so many skyscrapers.
"Running up stairs is safe, as long as it's conducted in a controlled environment," he says.
Vertical running has been criticised as bad for the knee joints. But Lobo does not agree.
"Progressive training can strengthen your quadriceps so your knee joints experience less pressure," he says.
The students hope to finish the race in half an hour, and focus on their HKDSE afterwards.
But before that, head swimmer Raymond says they have one more task. "We want to organise a gathering to share our experiences with other students," he says.
No doubt, their schoolmates will be inspired.