He has to pause for breath after barely a minute of walking.
But that is not stopping lung cancer survivor Teng Kee Chye from exploring Toa Payoh Central and its assorted eating places, just opposite his four-room flat.
"It's boring staying at home," the 81-year-old said in Mandarin.
"If I'm tired, I'll find a chair and sit down. Otherwise, I'll lean against the wall for a while. That's better than facing the television the whole day."
Mr Teng used to venture as far as Chinatown to people-watch, but being diagnosed with lung cancer put a stop to that.
He was referred to Touch Home Care services after he was discharged from hospital last month and Mr Teng now relies on physiotherapist Vivian Lim's weekly visits to combat his breathlessness and increase his strength.
Touch also oversees his meals, transport and housekeeping needs.
Initially, he would be panting just from walking from the bedroom to the kitchen.
Visiting a day rehab centre was out of the question, a Touch spokesman said, because Mr Teng could not go downstairs alone.
Mr Teng, a divorceé, used to live with his younger sister, but she died in January. His younger brother visits and stays over on weekends.
His frail condition belies a steely will.
When Mr Teng gets tired while exercising, he psychs his legs to carry on.
"I'll get angry and scold myself if I cannot continue," he said.
He is looking forward to getting fit enough to take public transport and stop home care in about two months.
With his determination, Mr Teng's goal of visiting Chinatown again may soon become a reality.
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