ZHENGZHOU, Feb. 1 (Xinhua) -- In a dimly lit room, Xu Yuanyuan stands on her tiptoes wearing a blue tutu, ready for the music to start. Only the creases around her eyes and her silver hair bun distinguish her from a typical ballet dancer.

Chinese pensioners are picking up new hobbies as they move into their golden years, and ballet has become a favorite pastime among the over-50 set.

Xu, 58, took up ballet early last year when a "silver swan" troupe was established in Zhengzhou, capital of central China's Henan Province. The troupe consists of 18 members with an average age of 55. The oldest is 62 years old.

"I was very excited as I won a grand prize when I was joined the troupe. It has strict requirements for a dancer's weight and height," Xu recalled.

The retirees faced their own set of difficulties as they learned the tiptoe dance techniques. Elderly people's bones and ankles are not as strong as those of younger people, and most of them lacked basic dance skills and performance experience.

The troupe organized ballet courses for older adults who would never otherwise have had the opportunity to dance. But it was not easy.

The first challenge was leg extension. As Xu lifted her left leg onto the barre slowly, her knees hurt and she always lost her balance.

Bigger trouble came from standing on her toes. She had to stop and massage her feet every ten minutes. Her toes were rubbed raw and she even had to have some toenails removed.

"It was a big pain," said Xu.

But ballet has become an indispensable part of her life. Whatever she is doing -- cooking, watching television or waiting for the bus -- she now unconsciously does on tiptoe.

Loneliness flooded Xu's life after she retired as a government agency employee. She is divorced and lives with her 90-year-old mother. Watching television and visiting the supermarket were her only daily activities.

"I felt dizzy and had difficulty falling asleep. Doctors suggested I do more outdoor exercise," Xu said.

Before taking up ballet, Xu fell in love with public square dancing seven years ago when she walked in local parks and discovered groups of elderly square dancers.

Square dancing in public squares has become a popular exercise among China's elderly and middle-aged due to its low costs and ease of participation.

There were about 230 million people aged 60 or over in China at the end of 2016, close to 17 percent of the population. More than half of them were "empty-nesters," who live apart from their children.

The growing senior population is a sign of the country's health and medical improvements. But the elderly need more entertainment choices to live happy, healthy, and social lives.

"Dance has improved my health and I feel younger now," said Xu. Many members of her troupe were square dancers, but a shared dream from their girlhood inspired them to shift to ballet.

"In fact, people of my generation first knew ballet, not square dancing," said Du Youling, head of the ballet troupe.

Chinese ballet operas such as "The White Haired Girl" and "Red Detachment of Women" were the highlight of her childhood. But she didn't have the money or opportunity to learn ballet when she was young.

"After I graduated from college and began to earn money as a teacher, I had a daughter. I had no time to learn then," she said.

For Du, retirement meant a new beginning. She finally had time and money to do what she liked -- playing the piano, yoga, folk dancing and ballet.

Photos of Du and Xu's troupe dancing went viral recently, and Chinese social media users called them "ballet grannies."

"We are growing older, but we can do it in a graceful way," Du said.