GLASGOW, Scotland (AP) At its base, underneath the glittery leotards, ripped abs and all that chalk, gymnastics is about pushing boundaries.
One more twist. One more rotation. One more flip. One more test of the laws of physics and your own mettle.
Doing something never done before under the lights and in front of the judges provides not just a shot at gold but also a kind of immortality: your name next to a particular skill in the Code of Points. Athletes at this week's world championships who submit a new skill and complete it successfully in competition could find it added to sport's governing body's rule book by the end of the meet.
Sure, medals are sweet. The code is forever.
When three-time all-around champion Simone Biles tries to add to her stash during event finals this weekend, her gravity-escaping floor exercise routine will include the ''Biles,'' a tumbling run that found its way into the code two years ago almost by accident.
Concerned about the pain in her Achilles every time she tried to complete her second pass with double-layout and full twist, Biles and coach Aimee Boorman decided to improvise. Rather than a full twist, Biles chose to do a half-twist and turn outward. Doing less sounds easier. It's not. The move required Biles to basically land blind because she can't see where her feet are in relation to the floor until the last second.
''It was almost kind of necessity is the mother of invention,'' Boorman said. ''Her calf was hurting. She had bone spurs in her ankles and she's really good at floor with landings.''
Biles took the combination to one of the U.S. national team training camps hoping to get a nod of approval from team coordinator Martha Karolyi and the rest of the staff. She did, kind of.
''They were like `OK, it's different but she lands it most of the time,''' Biles said with a laugh.
So Biles and Boorman videotaped it and sent it to the International Federation of Gymnastics before the 2013 world championships to let them know it was coming. Biles drilled it - and the FIG technical committee approved it, putting the description in the code with Biles' name next to it.
Getting into the code wasn't exactly the point when Biles and Boorman brainstormed. It was for Brenna Dowell. The 19-year-old spent a considerable amount of time working on her own aggressive tumbling pass, one that ends with a front double-pike. (Think somersaults with your arms wrapped around the back of your ramrod straight legs like a diver.)
Dowell pointed to worlds as a chance to get the bold move into the books. She nailed it despite having to do her entire routine without music due to a technical glitch, an accomplishment that helped take some of the sting out of later being benched by Karolyi for the team finals.
''I got it named after me, so that was pretty cool,'' said Dowell, who did take home gold after the U.S. won its third straight world title.
At the moment, the ''Dowell'' and the ''Biles'' belong solely to their namesakes. That's likely to change as the sport evolves. What is boundary-pushing when introduced can become passe over time.
It's a lesson Romania's Marian Dragulescu learned in his return to competition following a four-year layoff. The three-time Olympic medalist invented the Dragulescu vault a decade ago, a leap that requires two forward flips with an inward turn as you land. It helped Dragulescu win four world championship vault titles, the last in 2009.
The 34-year-old dusted it off in qualifying last week. The sight of Dragulescu literally ''Dragulescu-ing,'' had the gymternet - the sport's nickname for itself on social media platforms - having a temporary meltdown as a result. The judges rewarded him with a 15.4 for it, good enough to make the event finals.
Still, Dragulescu understands it might not be enough to reach the top of the podium. The difficultly value of his eponymous vault has decreased over time as newer, harder tricks have come along. He's been incorporating another half-rotation to it hoping it will be ready by the 2016 Olympics.
Maybe he'll call it ''Dragulescu 2.0.'' It would help clear up the momentary confusion that hits him whenever he searches his name on Twitter during a meet.
''I saw `Dragulescu' and I thought it's about me,'' he said with a laugh. ''And it's just about my vault!''
Follow Will Graves at www.twitter.com/WillGravesAP