SINGAPORE - A former lieutenant-colonel, an ex-public prosecutor and a retired hairdresser - all pushing 70 - stand among 25 others, sweating it out at Kent Ridge Park as the sun rises.
"Faster! Punch harder! Burn the fat away!" yells their volunteer exercise group leader, businessman Daniel Tang.
Watching the group go about their hour-long workout on top of the quiet, hilly park, it is hard to believe that the tough-looking Mr Tang, whom the group jokingly calls "sir", had any health problems.
Yet the 56-year-old used to weigh a hefty 108kg, and it took two kidney transplants - one in 1991 and another in 2003 - before it sank in that his lifestyle had to change.
"I thought it was a miracle that I had survived those transplants, and I wanted to start exercising to get healthier," said Mr Tang, who is married with two daughters in their 20s.
He does stretching and breathing exercises before each workday on the park's hilltop, working muscle groups from his face down to his legs.
A decade on, that ritual has helped him shed about 30kg to attain his current 75kg frame, which he hopes to maintain through signing up for the One Million KG Challenge.
It has also grown from a one-man daily regimen into a voluntary community exercise group attracting people in their 40s to 80s.
When The Sunday Times popped by for a recent session, the group numbered 29 - most of whom were retirees living in the Kent Ridge neighbourhood who enjoyed the low-impact exercises Mr Tang had put together.
There was also a couple in their mid-50s, Madam Susan Lim and her husband Chan Siow Boon, who jog 7km from Redhill to the park each day just to take part.
Anyone is welcome to join him, said Mr Tang, adding that his little following has surprised him as he had never intended for it to be anything more than a personal programme to get fit.
"It's nice to see so many people interested in living healthily," he said. "If people have healthy bodies, they have healthy lives, and healthy families. Life is so short, you must treasure your days and live well."
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