In 1995, Lang became head coach of the Chinese national team and guided the squad to a silver medal at the 1996 Summer Olympics in Atlanta and second place at the 1998 World Championships in Japan.
Lang took a coaching position in the Italian professional league in the following years, where she won multiple league championships and the coach of the year award.
She became coach of the US national team in 2005, and guided the team over China, 3-2, in a Beijing Olympic game that drew 250 million television viewers in China alone. The US went on to win the silver medal at the Games.
Lang joined Chinese volleyball club Guangzhou Evergrande in 2009, and has led the team to one league championship and two runner-up finishes in three seasons.
She is expected by the State sports authority to guide the team to a podium finish at the Rio Summer Olympics.
Still, it was a difficult decision.
"It wasn't easy for me to make the decision, maybe the most difficult one, and my biggest concern is whether my body can handle the workload," said Lang, who resigned from the national team in 1998 for health reasons.
Former teammate Yang Xi said changing coaches won't cure Chinese volleyball; rather, youth training needs to be improved.
"Lang Ping inherited the dedication and fighting spirit of women's volleyball, which is worthy of praise," Yang said. "But to really make improvements, we should look outside the national team and focus on modifying the youth training system at the local level, instead of expecting one coach to make drastic changes."
Lang is also aware of the problems facing her.
"Chinese volleyball is facing many difficulties," she said. "We are short of both volleyball population and distinguished athletes and we have a lot of work to do, but as long as we work together to overcome the hardships, I have confidence and the determination to accomplish our goals at the Rio Olympics.
"We will work closely with the local coaches, and improve the competency of players both on the national team and clubs. We will work out a new national lineup as soon as possible, discover the potential of each player, and adjust our strategy through training and matches."
Lang will lead Guangzhou Evergrande as it plays in the Asian Women's Club Volleyball Championship on Monday, and take over the national team after that.