Leng's first international medal came at the 1990 Asian Junior Athletics Championships held in Beijing. She won the 400 m hurdles gold medal with a time of 57.79 seconds. This stood as the championship record for over a decade, finally being broken by another Chinese hurdler, Wang Xing, in 2004.[1] She emerged as a senior athlete at the 1993 Chinese National Games with a performance of 54.52 seconds to claim third place in a race won in an Asian record by Han Qing.[2] This time ranked Leng tenth in the world for the event that season.[3]
Her senior international debut followed a few months later at the 1993 Asian Athletics Championships. At the competition in Manila she led the Chinese challenge in the 400 m hurdles and took the silver medal behind Kazakhstan's Natalya Torshina.[4] In 1994 she won her first and only national title at the Chinese Athletics Championships with a time of 56.28 seconds.[5] This gained her selection for China at the Asian Games later that year.
Leng defeated both Torshina and Hsu Pei-Ching of Chinese Taipei to become the Asian Games champion in the 400 m hurdles. She was the third Chinese woman to win the title, after inaugural winner Chen Xin (諶欣) and Chen Juying, who had won the previous edition.[6] Her winning time of 55.26 seconds was an Asian Games record which lasted for twenty years. It was finally bettered in 2014 by Kemi Adekoya (a Nigerian-born runner for Bahrain).[7][8] Originally, Leng had finished as runner-up to Han Qing, who was subsequently disqualified and banned for doping.[9] She ran the lead-off leg of the 4×400 metres relay in a Chinese team of Zhang Hengyun, Cao Chunying and Ma Yuqin and the quartet won the gold medal in a Games record of 3:29.11 minutes (Leng's second of the tournament).[10] Despite being only 22 years old, this was the last major medal of her career and 1994 was the last time she ranked in the top twenty athletes globally.[11]
