BEIJING - The head of China's gymnastics team has urged the FIG to modify rules for the sake of athletes' health after an Achilles injury ruined three-time world vault champion Cheng Fei's bid for the London Olympics.

Cheng, the captain of China's gold medal-winning team in Beijing Games four years ago, underwent an operation to repair a ruptured Achilles on Thursday and could not recover before the July 27-August 12 Olympics.

"Despite wearing tendon protectors, Cheng still tore her Achilles during a training session," said Chinese team leader Ye Zhennan.

The 24-year-old Cheng is the latest casualty of injuries. Earlier this month, US Olympic gold medalist Shawn Johnson ended her comeback for the 2012 Olympic team and retired because of her constant problems regarding her left knee.

Ye, who has repeatedly emphasized the importance of safety on several occasions, blamed FIG for giving too much credit for difficulty, which led to frequent injuries and shortened career of girl gymnasts.

"Not only China, but other teams including Russia and the United States face injury woes," he said. "It's time for the FIG to make some changes to the rules."

Cheng made her fame at the 2005 World Championships in Melbourne, Australia, when she became the first female gymnast ever to successfully execute one of the most difficult vaults.

A vaulting and floor exercise specialist, Cheng pocketed one gold and two bronzes from the previous two Olympic Games - Athens 2004 and Beijing 2008.

She was forced out of the sport due to injuries after the 2009 National Games and returned to international competition for the first time in three years in April, winning the vault title at the World Cup in China.

"After the National Games in 2009, I decided to take a break due to my knee injuries. I totally lost in depression and emptiness these years. It's my irresistible desire to compete in another Olympics that pulls me out of the shadow," recalled Cheng.