By Pritha Sarkar

LONDON (Reuters) - Performing gravity-defying stunts on a daily basis should provide enough of an adrenaline rush to last a lifetime.

For gymnast extraordinaire Simone Biles, that simply is not daring enough.

"I plan on doing things that I can’t do because of gym right now. Crazy things like going swimming with sharks or jumping off a cliff into water," American teenager Biles told Reuters in a telephone interview as she outlined her post-Rio Olympic plans.

For most people, Biles's daily ritual of performing aerial acrobatics for hours on end, as she perfects her routines on the beam, vault, floor exercise and asymmetric bars, would amount to doing "something crazy".

For an athlete who is already being tipped as the greatest ever female gymnast even before she makes her Olympic debut in August, competing in global arenas is like child's play.

Since making her debut at the 2013 world championships, the 19-year-old has become an unstoppable force. Last year she became the first woman to win a "three-peat" of all-around golds at the worlds.

"I just wish I could see it for myself the way you guys see it because for me it’s normal, it’s something I do every day," said Biles.

"Sometimes when I watch (my performances on YouTube) I think it’s unreal. How is it possible that I can chuck myself in the air and do all these tricks and land them?

"I blow my mind as I don’t understand how I do it sometimes."

She has been blowing everyone's mind during the current Olympic cycle.

Her talent was clear for all to see at the last three world championships -- in Antwerp, Nanning and Glasgow -- as she flew through the air faster and higher than her rivals, completing her acrobatic tumbles with solid landings.

Those skills also helped the gymnast nicknamed '$imoney' to become the most successful female athlete at the worlds -- with a record haul of 10 gold medals.

MENTALLY STRONG

"To me records prove how mentally strong and powerful you are and how well you can handle pressure," said Biles, who was adopted by her grandparents 16 years ago after her mother struggled with drug and alcohol addiction.

"It’s inspiring to young athletes that there are records that can still be broken. It’s never over, there is always something else you can do to do more."

She will be trying to do just that in August.

Such is the American's standing in the sport that she is the overwhelming favorite to complete a feat that no woman has pulled off for 20 years -- winning back-to-back world and Olympic all-around titles.

Since the all around event was introduced to the Olympic program in 1952, only three women have bagged the double -- Soviet Union pair Larisa Latynina (1960) and Ludmilla Tourischeva (1972) and Ukraine's Lilia Podkopayeva (1996).

So why does the 1.45-metre dynamo think no one has done the double since 1996?

"I wasn’t born earlier, so I had no say in that!" quipped the 1997-born gymnast.

Too young to compete at the 2012 Olympics, she was one of millions of American viewers who were glued to their television screens as her now team mate Gabby Douglas struck gold in London.

Biles's date of birth dictated that she became a senior at the start of the current Olympic cycle, meaning that if she wanted to have a shot at Rio glory she would have to sustain her levels of excellence for a full four years -- a stretch that is beyond most elite gymnasts.

Thanks to the meticulous planning of her lifelong coach Aimee Boorman, who mapped out "a balancing act of keeping Simone healthy and making sure she has fun", Biles has avoided the pitfalls of peaking too soon or suffering burnout.

With so much natural flair oozing from every pore in Biles's body, celebrated coach Bela Karolyi observed: "I've never in my life seen a more talented, more agile and more potentially capable young lady than Simone."

That is high praise indeed considering Karolyi was the man who steered Nadia Comaneci to the first perfect 10 at the Olympics, helped Mary Lou Retton to become the first American to win an Olympic all-around gold and was the guiding force behind Kerri Strug's heroic vault at the 1996 Games.

For Biles, the real thrills lie in wait once the Olympic flag is folded away on Aug. 21 and she gets a chance to get up close and personal with Jaws.

"Swimming with sharks will probably happen in Belize and jumping off a cliff, that can be anywhere!"

(Editing by Clare Fallon)