She said that back then she could not move about, chat with other residents or even ask a nurse for help to go to the toilet. Now 82, her life is completely different.

She is no longer bed-bound or restrained. She can sit up for up to six hours a day, walks about using a walking aid, and exercises using rehabilitation machines that involve light weightlifting and stretching.

“Being out of bed and able to walk again is such a liberating experience,” said Cheng, who has only one child, a daughter who is unable to care for her at home. “Now the pain from being strapped is gone and I can do things without having to depend on others.”

She continued: “Now I smile more often, my daughter is happy too, it’s like I’ve been given a new lease of life.”

Her turnaround occurred after she moved in May 2017 from the first care home to an elder care facility run by the Christian Family Service Centre, a local non-government organisation.

There, she underwent the centre’s “self-support” rehabilitation programme, which had less restraints, less time in bed and less use of adult diapers. It also placed greater emphasis on physical exercise and helping the elderly to look after themselves.

A year after she moved there, she said she was a new woman and able to move about.

The centre’s managers decided to find a way to help elderly people like Cheng after realising that many care homes kept members immobile and strapped to their beds and wheelchairs because there was not enough staff to look after them.

About 33,000 elderly people live in residential care centres in Hong Kong, according to latest official figures.

In a high-profile case in 2016, the police investigated a case of possible abuse at a care home after photos emerged showing residents tied to toilets.

To show how the programme works, the centre invited 30 nurses and carers from other institutions to spend three hours role-playing what it is like to be an elderly person in a care home. Some of the participants had tied up elderly residents themselves, or witnessed the practice elsewhere.

Among the participants was Jason Wong, a 24-year-old exercise physiologist who had been working at a local institution for six months and had seen elderly people in restraints.

During the session, he and the others were strapped and bound and kept blindfolded so they could understand the experience of elderly people with poor eyesight.

“It was very uncomfortable losing my freedom and feeling left at the mercy of my carers,” Wong said afterwards. “I tried to sleep but couldn’t, because Chinese opera was playing to simulate a care home environment. Worst of all, I felt scared when I was pushed around in a wheelchair, blindfolded. I had no idea what hour it was or when I would be freed.”

He said the experience gave him a new perspective and he pledged to pay more attention to the needs and feelings of his patients.

But Labour Party lawmaker Fernando Cheung Chiu-hung, who is a registered social worker, said compassion and the expertise of carers was not enough.

“Carers often tie residents on beds because they have too much work to do,” he said. “There are too few of them to attend to residents’ needs and make sure they don’t fall down and hurt themselves, or even take them to the toilet. That’s why they put diapers on the elderly.”

In the financial year 2018-19, the Hong Kong government spent HK$352 million on elder care, rehabilitation and children’s home services, with most of that amount going to staff salaries.

Cheung said the government was not spending enough on care for the elderly. The care facilities need more support, he said, to employ enough staff to care for their residents.

“Hong Kong is one of the wealthiest places in the world,” Cheung said. “Surely, we can afford to let our old people live the end of their lives with dignity.”