PARIS.- When gymnastics superstar Simone Biles tumbles and dances her way through her third Olympics this month, the choreography she performs in her floor routine will be seen on hundreds of millions of screens around the world.

Grégory Milan, the man who created it, still shakes his head at its reach. “I can’t quite fathom it,” he said recently at the National Institute of Sport, Expertise and Performance, or Insep, in Vincennes, a suburb of Paris, where he works as a full-time dance instructor for the French national team.

The Biles effect has brought with it something unexpected for Milan at 51: success.

Until now, Milan, a dancer and choreographer, has considered his life to be “a series of failures of sorts,” he said wryly. When he turned to gymnastics choreography full time, in 2017, he was in debt, having started a dance company that never took off, and still reeling from the psychological scars left by a tumultuous career in ballet.

“I was furious with what I’d experienced in the dance world,” he said. “I loved the art form so much, but the behavior of the people I’d encountered in it disgusted me.”

Gymnastics has become an unlikely balm. His pure dance background is unusual in the sport: Most choreographers who work with gymnasts are also coaches and former athletes, who have an affinity for dance or have had some dance training on the side.

Alisée Dal Santo, a coach and choreographer who works alongside Milan at Insep, said in an interview that “it’s difficult to find choreographers who can fit into this world, because it’s quite restrictive.” She pointed out the need to understand the Code of Points, the rule book that governs gymnastics’ judging system: “You have to build choreography around all the required elements.”

For Milan, that was especially true of his routine for Biles, 27, who performs four high-difficulty tumbling lines on floor. “It means she has to be really at ease,” he said. “She was on ‘Dancing With the Stars,’ and I could tell that she moved really well. But when she goes into gymnastics mode, she is more reserved because she is thinking about the acrobatics.”

The two first met in 2022, when Milan traveled to the World Champions Center, Biles’ home gym, in Spring, Texas. His assignment was to create a floor routine for French gymnast Mélanie De Jesus Dos Santos, who moved to the United States to train with Biles’ French coaches, Cecile and Laurent Landi.

“Simone saw what I was doing, and she liked it,” Milan said. When he returned this past winter to create another routine for De Jesus Dos Santos, Biles asked to work with him, too. He created her Olympic floor routine in just six days.

For the 90-second exercise, which features music by Taylor Swift and Beyoncé, he was inspired by choreographer Alvin Ailey. “I wanted to give her spare, mature, commanding choreography, because she’s not a little girl anymore. She is the boss, a Black woman who is doing so much for her country, and she shouldn’t be afraid to show it.”

Biles was an active collaborator. “She is so levelheaded and normal, but she knows what she wants,” Milan said. “When she says no, it means no.” The routine, which she performed twice at the U.S. Olympic Team Trials in Minneapolis in June, helped Biles secure her ticket to the Paris Games.

Although Biles’ floor exercise will bring him outsize exposure, Milan said that when he started working with gymnasts in the early 2010s, “there was no consideration” for choreographers. A coach from his hometown, Saint-Étienne, a city just west of the Alps, had asked him to come and help at the local national training center. Milan quickly realized that “you’re basically nothing in this world when you come from dance,” he said. “When gymnasts go to dance class, the feeling is that it’s relaxation time.”

Yet, Milan became convinced that dance was crucial to a gymnast’s overall quality of movement: “Dance classes help them understand their body, find stability, refine their contact with the floor.” At the World Champions Center, which doesn’t have a permanent dance coach, he had Biles and her teammates working on “more contemporary diagonals, walking, relaxing the body.”

“It’s not just about adding choreography to a routine,” he said. “Dance should come earlier in their training.”

His exuberant presence is a breath of fresh air for athletes used to highly regimented training. De Jesus Dos Santos, a world and European medalist who is one of the stars of the French national squad, met Milan when she was 12, in Saint-Étienne. “What I immediately loved about him was that he is genuine,” she said. “He says what he thinks and isn’t afraid to be himself.”

For Milan, dance was a way to express himself as a child who “felt different” from others. His parents, a fireman and a teacher, were tough, he said, although they supported his passion for ballet. At 11, he was accepted into the prestigious Paris Opera Ballet School, and spent what he called his “happiest years” there, even relishing the iron discipline of the school’s director, Claude Bessy. “It wouldn’t fly now, but I loved her strictness,” he said. “She was like a mother and confidant to me.”

He faced a brutal blow to his ballet dreams in 1991, when he finished third in the entrance exam for the Paris Opera Ballet, with only two contracts on offer. “I felt completely abandoned from one day to the next, because the school didn’t prepare you to get into another company,” he said. “They just dropped you.”

To this day, Milan said, he has “trouble walking past the Palais Garnier,” where the Paris Opera Ballet performs. “I get a knot in my stomach. The grief has never gone away.”

Still, he kept dancing. For four years, he was a member of Victor Ullate Ballet in Spain, which at the time boasted international stars such as Ángel Corella. In 1995, he moved on to the Ballet de l’Opéra National de Bordeaux, in France, where he achieved the rank of soloist.

His career came to an abrupt halt just over a decade later. At the time, the director of the Bordeaux company, Charles Jude, was sued by a female soloist for workplace harassment. Milan was one of two company members to testify in her favor in court. Both dancers were let go when their contracts came up for renewal — a form of retaliation in Milan’s eyes, since the same administration had promoted him to soloist not long before. (The company declined to comment.)

Bruised from the experience, Milan ultimately returned to Saint-Étienne, where he spent four years trying to get a company off the ground. The city promised some funding, and then withdrew. “I poured all my money into that project, got into debt,” Milan said. “I couldn’t go on like that.”

And so he turned to gymnastics.

In 2017, he was hired at Insep, where he gives daily classes — a modified ballet barre incorporating gymnastics moves — to top rhythmic and artistic gymnasts, who know him by his nickname, Greguito.

In a recent class, he doled out praise and corrections with trademark flamboyance, asking his charges to aim for more extension and precision. “Don’t start,” he told one with affection when she looked annoyed. “You started!” she replied, joking with him.

His floor choreography has helped to lift the French team on the international stage. “He brings a sense of openness,” said Dal Santo, the coach and choreographer, “whereas we can get stuck in a routine because gymnastics requires so much discipline.” For the floor exercise of Morgane Osyssek, 21, a member of the French Olympic squad, Milan found inspiration in a landmark work of contemporary ballet: William Forsythe’s “In the Middle, Somewhat Elevated,” created for the Paris Opera Ballet in 1987.

When Milan first played the ballet’s electronic score — a crashing, propulsive composition by Thom Willems — Osyssek “thought he was joking,” she said in an interview. “I had a hard time picturing it as floor music, because it’s not at all what we’re used to.” The first reaction of many in the gymnastics community was also negative, she said. “But then we started working on the movement, and I realized it worked really well.”

Dance may not have given him the recognition he sought, but Milan now has a platform most choreographers can only dream of. In an Instagram story in May, Biles paid tribute to his singular role in gymnastics. “Your energy is electric!” she wrote. “Everyone needs a Greguito in their life.”

This article originally appeared in The New York Times.