Simone Biles 'not ashamed' and 'not afraid' as Russian hackers reveal ADHD treatment

US gold medal winning gymnast Simone Biles has spoken out after hackers revealed she took medication for ADHD.

She was named among a number of athletes who take medication that is usually banned in sports.

Theraputic Use Exemptions allow individuals to take banned substances if required for specific medical needs.

Documents leaked by hackers apparently show the star tested positive for methylphenidate, better known as Ritalin, in August this year.

Simone, who won four golds in Rio, has defended herself on Twitter and has stated that the drug does not give her an unfair advantage.

Simone Biles insists she has followed the rules.

She also tweeted a more personal message, addressing her feelings about living with the condition.

She says she is not "ashamed" of having ADHD.

People with ADHD (attention deficit hyperactivity disorder) struggle with their attention span and can have issues with behaviour and activity levels.

Ritalin works to increase concentrations of dopamine and norepinephrine in the brain.

Side effects can include weight loss, nausea, insomnia, lethargy and dizziness.

Some claim it can cause growth issues if used to treat young children.

The USA gymnastics governing body has issued a statement supporting Simone Biles.

It says there has been no violation of the rules.

Simone Biles is one of many successful athletes with ADHD, including Michael Phelps and GB athletes Louis Smith and Ashley McKenzie.

Tony Lloyd, CEO at the ADHD Foundation in the UK, says Simone's statement on the condition is a positive message to young sufferers everywhere.

"It challenges that myth and stereotype that anyone with ADHD is an under-achiever or has behavioural difficulties," he tells Newsbeat.

"It sends a very clear message to people out there that having ADHD doesn't mean you can't achieve your potential."

Simone was one of the most talked-about stars at Rio 2016

He also tells us that Ritalin should not be considered alongside performance enhancing drugs, banned by sporting authorities.

"I don't see that taking ADHD medications would give an athlete an advantage," he says.

"What ADHD meds do is enable people to concentrate and be more focused. That's very much around cognitive functioning, it's not about athletic prowess.

"When you're doing lots of daily physical exercise, that in itself affects the brain in such a way that it lessens the impact of your ADHD.

"So in a sense, you self medicate through exercise."

It's been suggested the hack on medical records is retaliation from Russia after its athletes were banned from the 2016 Paralympics.

Russia has strongly denied the claim.

The country was barred after doping concerns led to 267 Russian athletes being stopped from competing.

You can find support and information about ADHD on these BBC Advice pages.

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