1 .     1    . The legendary volleyball coach Lang Ping gave the answer in the recent documentary (纪录片) The Iron Hammer.

The documentary displays Lang’s inspiring journey from her gold medal victory as a volleyball player in the 1984 Olympics to her amazing career as a successful coach for both Team USA from 2005 to 2008 and China since 2013. She was the first person to win Olympic volleyball gold as a player and coach. Lang Ping revealed the secret to such remarkable achievements in the documentary. As she said, “    2    ”.

    3    . Troubled by severe injuries to her cervical vertebra, back, waist and knees, caused by intense exercise and hard work, the 60-year-old has undergone more than 10 surgeries. “No parts of my body function well,” she joked.

But illness is certainly not the only difficulty Lang has faced. In 2005, she struggled with balancing raising her daughter Lydia Bai Lang, who lived in the US, and her coaching career. She eventually decided to work for USA Volleyball that year.     4    “I’m proud of being Chinese”   Lang responded in an interview. Later she returned to head the Chinese women ’s volleyball team in 2013, leading the team successfully defending its World Cup crown with a perfect record of 11 straight wins last year.

There is no doubt that Lang is one of the greatest players and coaches in history. As an American athlete commented in the documentary,     5    .