A diagnosis of prostate cancer more than 10 years ago never slowed Mr Sng Tian Kee down.

The badminton coach still exercises almost every day, coaching at the United World College four times a week, playing with a friend once a week, and teaching his grandchildren the game.

He has played badminton for 70 years and still loves it, said the 81-year-old.

On top of that, Mr Sng also practises luk tung kuen, a Chinese exercise similar to taiji, at the Botanic Gardens four times a week.

"My advice (to cancer patients) is to keep yourself busy. The best medicine for everything is exercise."

After his diagnosis in 2005, he had an operation to remove the entire prostate gland. A year later, doctors advised him to have radiotherapy to kill the remaining cancer cells.

"I continued my active life and don't think too much of it. I even picked up new skills like playing the ukelele," he says.

One thing he will not do is to change his diet.

"I hate veggies, so I tell my wife, don't force me to eat. I'm also borderline diabetic, but I have a sweet tooth. And I also still love my char kway teow and bak kut teh," said the father of three.

His doctor, Dr Ravindran Kanesvaran of the National Cancer Centre Singapore, says his condition is stable for now and is being controlled with ongoing treatment.

Every two to three years, Mr Sng does a CT scan to check if the cancer has spread to the bones.

His biggest fear: losing his mobility. "I'm afraid of falling and not being able to maintain my active life anymore."

Find out more about cancer and how to fight it on ST's Fighting Cancer microsite.