As the beat of Psy's latest Korean hit poured out of the speakers, Madam Teo Wee Peng, 72, swung into action.
She and 30 other seniors waved their arms, spun and stretched side to side.
"Line dancing is too vigorous for me," said the retiree. "This is just nice."
This is the latest addition to a Tan Tock Seng Hospital (TTSH) project to prevent falls among the elderly. Since the end of last year, dancing was included to liven up the basic exercise programme and encourage regular attendance.
"It's hard to keep people on an exercise regime for a long time," said Dr Noor Hafizah Ismail, head of TTSH's falls prevention clinic. "We were trying to make it a bit more interesting."
Those who sign up go through a series of screenings to check their eyesight, blood pressure and balance, among other things.
For exercises, they are split into groups depending on their level of mobility.
Part of the National Healthcare Group's community outreach efforts, the scheme has reached out to 1,154 seniors since 2009. There are now 413 participants on the programme.
Falls are a serious issue for the elderly. The consequences are more severe for those over 65.
About 10 per cent of this group get injuries such as fractures, and may even become permanently disabled.
At least 50 per cent of those with hip fractures, for example, never regain their pre-fall state of health, said Dr Hafizah.
Falling can also be a symptom of something "more sinister".
Frequent falls may be a result of medication which causes giddiness or drowsiness, or even degenerating vision.
"People take falls for granted because everyone has fallen," Dr Hafizah said.
"But falls among the elderly are not always accidental."
TTSH's fall prevention programme is not just about exercise. Hospital staff also pay home visits to identify hazards such as slippery rugs or wet floor tiles, and ensure devices like grab bars are being used correctly.
"Sometimes, when they don't know how they are supposed to use grab bars, the bars end up as towel hangers," said TTSH senior nurse manager Alicia Gan.
While getting seniors to open their homes to strangers is sometimes difficult, a little peer pressure usually does the trick. "When they hear their friends talking about it, they also want to participate," she said.
After a spinal operation about eight months ago, Madam Teo, who was worried that another fall would further damage her back, signed up for the programme in September.
She has been taking part in line dancing at a senior activity centre for the last eight years.
"In line dancing, we used to go non-stop for an hour, with lots of turns and steps," Madam Teo said. "This is very mild in comparison." But she was still apprehensive when the first class rolled around.
"I was very stiff, and I was really frightened to move too much at first," she said.
"But my doctor said that I must exercise."
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