Biles is strongly tipped to add to her cache of four Olympic golds at the Paris Games after a tumultuous Tokyo campaign, when she withdrew from most of her events as she battled the dangerous and disorientating "twisties".
After a near two-year absence, Biles has reestablished herself at the top of a sport she redefined with a unique combination of athleticism and artistry.
Meticulous attention to her mental health has the 27-year-old heading into her third Olympics on her own terms.
"Nobody's forcing me to do it," Biles said after earning her Paris berth. "I wake up every day and choose to grind in the gym and come out here and perform for myself -- just to remind myself that I can still do it."
Biles nailed a spectacular Yurchenko double pike vault, sticking like glue on the landing. It is a skill so difficult that no other woman has attempted it in competition.
She and her US teammates were all business as they got a feel for the competition arena, opening on balance beam, where Biles delivered some solid tumbling elements.
Moving on to floor exercise, Biles wowed with her triple-twist double flip but was a hair off in landing several of her impressive tumbling skills.
That took the Americans to the vault, where she offered a glimpse of just what everyone else in the field will be up against.
Biles closed out the session on uneven bars, high-fiving coach Laurent Landi after completing her routine.
The session also offered a look at team medal contenders China and Italy as well as Algerian teen Kaylia Nemour, who has emerged as a gold medal threat in uneven bars.
Host nation France and the Brazilian squad led by vault world champion Rebeca Andrade were due to train later Thursday.
Women's competition opens on Sunday with the qualification round, with their first medals to be awarded in the team final on Tuesday.
The women's individual all-around final is on Thursday, with the individual apparatus finals to follow.
