Sudanese trainees do trick-cycling acrobatics during daily training. [Photo provided to China Daily]

"She is such a cool girl who likes to mix the rhythms of pop music with gymnastic movements, and I think it is a breakthrough for acrobatics," she said, smiling.

Mohamed did not expect to revisit China at all, until she got the invitation letter from an officer of China's Ministry of Culture one night in September.

She was overcome with joy reading the letter, she said. "China has undergone such tremendous changes in many aspects over the past four decades resulting from its reform and opening-up policy, and I couldn't wait to see those miracles, and most of important of all, my kind instructors.

"The moment I saw my instructor Yao Jinmei, I was moved to tears. The feeling of long-awaited reunion was so amazing. And I hugged her tightly," she added.

Born in 1938, Yao Jinmei was called "Mother Yao" by Sudanese acrobats, due to her professional teaching standards and meticulous care for each trainee.

"At first, I felt pressure after accepting the task to coach these foreign children. Cultural differences, the language barrier and homesickness were all a big challenge for me," Yao recalled. "I still remember the astonished look they had when they saw the Chinese acrobats set an example for them. But I kept telling them Rome was not built in one day, so they have to be persistent and patient."

According to Yao, Sudanese acrobats had a tough training life in Wuhan, as the city is burning hot in summer and freezing cold in winter. They had to train in a single posture again and again in such conditions. "If they want to succeed in the future, they have to endure the hardships. After all, no pain, no gain."