The arrest and conviction of former Penn State football coach Jerry Sandusky, brought to light a problem that experts say is affecting more than 39 million Americans: sexual abuse.  But for one Olympic hopeful, it was more than just headlines.

World champion Kayla Harrison is using her weakest days to make it all the way to the top.  She's on the 2012 US Judo Olympic team and she's vying to become the first American woman to bring home an Olympic gold medal in Judo this summer.

But for three years, she lived with a secret.  She was sexually abused by her former coach when she was 13 years old.

“I didn’t know what to do, what to expect or what to say,” explains Harrison.

An investigation by ABC's "20/20" revealed 36 swimming coaches were banned by USA swimming for allegations of sexual misconduct.  Last year Don Peters, who coached the 1984 US Olympic gymnastics team, resigned amid allegations of sexual abuse.

“It’s no longer a secret that just happens behind closed doors,” says Dr. Debra Day, a licensed psychologist.

Day says often young girls are groomed into a sexual relationship before they even realize they are involved in it.

"They become distorted in what they believe is happening,” says Day.

Harrison says she thought she was in love.

“In my mind it was a full blown relationship.  I was brainwashed.”

Experts say often a power paradigm is involved.  Predators will start to make the victims feel like they are more special than their peers.

“I spent every minute with Daniel and he was really good at making me feel like he was the only one I needed,” says Harrison.

The National Council of Youth Sports has been trying to find the best way to screen coaches for at least a decade.  And the US Olympic Committee also announced it would centralize and standardize background check programs across all 32 Olympic sports.  But Day says parents can help by looking for unexplained behavioral changes in their child and asking questions.

Harrison did what most victims can't do.  She pressed charges and faced her abuser in court back in 2008.  Daniel Doyle was sentenced to 10 years in federal prison and banned from Judo for life.

“He turned around and he said ‘I love you’ and then I never saw him again,” says Harrison.

She turned her dark days into a positive, ranking second in the world.

“Although it feels like you are in a prison and you can’t get out, you can and there is help out there and there are people who care,” she says.

And she's taking that new found strength all the way to London. 

“I’m mentally tougher than anyone I know and that’s why I’m going to win the Olympics,” says Harrison.

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