The pressure was on.

Everyone was excited to see what Olympian Shawn Johnson would accomplish.

It was just one month until the Olympic games in London. Sponsors were piling up, friends and family anxious to see if Johnson could improve from her performance in 2008 in Beijing.

But no one knew what was going on inside the four-time Olympic medalist's mind but her.

Pain.

In a short film on the website IAmSecond, Johnson revealed how the pain she was suffering began to build during competition while competing in the 2008 games.

She had heard a competitor's score in relation to hers, and she realized it was impossible to win a gold medal in the event after she was projected to win four.

Later, as she stepped on the second highest step on the podium to receive her silver medal, she lowered her head.

"I remember being given the silver medal on the podium. The person that did it gave me a hug and told me, 'I'm sorry.'"

Those words would haunt her.

"It was kind of like a validation in my heart that I had failed," she said. "I felt like I had failed the world."

Johnson was just 16 at the time and the anticipation and pressure that had led up to her competition was what ultimately crushed her. It continued to do so even after she did win a gold medal later in the games. But it didn't matter - she did not feel like she had lived up to everyone's expectations.

"If I failed at being a gymnast, I'd fail at being a human being," she said.

The pressure carried over into her training for the London games. She was not 16 anymore and was scoring all-time career lows.

"I remember I was losing hair. I wasn't able to sleep. I wasn't eating properly. I was struggling with that I wasn't 16 any longer," she said.

Finally, one day, about a month away from the Olympics, she was on the beam. Her best event. And as she looked down, she said she had an epiphany as a result of her Christian faith.

Being a gymnast did not have to be her purpose in life. Rather, she said she found a greater reward than winning gold: following God.

She decided to end her career.

Johnson really had never opened up about her sudden retirement until the film, which was released on July 12. It is part of a series of films featuring dozens of athletes and celebrities that have dealt with various forms of depression for various causes.

The site encourages people to tell their story and create a helpful dialogue with those who suffer from depression.

In the film, Johnson also discusses how the reality television show Dancing with the Stars contributed to her struggle because of wide-spread criticism regarding her weight and appearance.

Watch the full film here:

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