The 19-year-old was the darling of the Games, winning four gymnastics gold medals and dazzling the watching world with her skill and sunny temperament.
Her excellence proved the early pinnacle of a journey that presented Biles with formidable obstacles, not only in terms of her early family life, but also her own body image.
It can be a touchstone issue for teenage girls in the sport, their muscular physiques marking them out as different to their peers, and Biles says she was teased at school, mostly by the boys.
“I think in the gymnastics world, it is your body figure because you get a little bit shy about your body because you are very muscular,” Biles told CNN when asked what was the biggest personal challenge she has had to overcome.
“But we wouldn’t be able to do the things or achieve the things we did without our bodies so we’re very grateful for them.”
If her tumble skills look effortless, Biles’ ability to shrug off taunts about her body shape only came through some painful experiences.
In a 2016 interview with CNN, Biles explained: “Going to public school nobody really had a body build that I did, and I was a girl, so the guys would sometimes make fun of me.
“I think they were just jealous because they didn’t have the muscle definition I did. I would try to hide my muscles, not show them, and I would always wear a jacket.”
It’s just another strand of the intense scrutiny Biles has been under since her Olympic success.
After taking gold in the all-around, vault, floor and team competitions, as well as winning bronze in the beam, the conversation around her looks intensified, leading to negative comments on social media.
It prompted her to hit back at her accusers: “You all can judge my body all you want, but at the end of the day it’s MY body. I love it & I’m comfortable in my skin.”
Two of Biles’ gold medal-winning teammates from Rio have encountered similar problems.
Gabby Douglas, a gold medal-winning teammate of Biles, suffered at the hands of online trolls and Aly Raisman has described as “completely normal” her feelings of insecurity relating to her body.
If Biles encounters any element of insecurity relating to her ability, recalling that brilliance in Brazil should help.
Never before had a woman from the US won four gold medals at a single Olympics, and her complete haul of five medals in Rio cemented her status as America’s most decorated gymnast.
Biles’ difficult upbringing has been well documented, but key to her success has been positive role models within her extended family.
She was placed in foster care aged just three due to her mother Shanon’s ongoing battle with drug and alcohol addiction.
In 2003, Biles and her sister Adria were adopted by her grandparents, Ron and Nellie Biles and moved to live with them in Spring, Texas, while her two brothers moved in with Ron’s sister.
The grandparents’ influence was pivotal in Biles’ early life and she credits her adoptive mom and dad as being one of her biggest inspirations.
“Outside of gymnastics it was my parents because they’re such good role models,” she said.
“They’ve never steered us wrong and they’ve always let us choose what we’ve wanted to do and they would just help us guide that the best way they could.
“And then in gymnastics either the 2008 or 2012 Olympic Team because we wanted to be just like them.”
Her journey to gold was down to a field trip visit to a gymnastics studio in Houston as a schoolgirl.
Biles returned home with a note suggesting she be enrolled into a class such was her natural aptitude for the sport.
By the time she was 13, it was decided that home schooling would be the best to fit around her training regime, which was upped to 32 hours a week.
Her promise was clear for all to see but after a wobbly performance at an event in 2013, the family enlisted the help of a sports psychologist to help her with big-event nerves.
The rest is history. So what has had the biggest impact on her career?
“I think it’s not just one person,” she said. “I think it takes a whole team that impacts my whole entire gymnastics career.
“It really does take an army to get you where you are. So I would say it’s a combination of my parents, my family, my friends, my coaches, my mentors.
“I have a great agent. So it takes a huge group and it’s not just one person.”
Biles’ exploits at the Olympics catapulted her to stardom and opened a number of doors back home.
A predictably successful stint in “Dancing With the Stars” — one of America’s biggest shows — saw her exit in the semifinal, but only after receiving two perfect scores for her routines.
She’s achieved so much at the tender age of 20, but what advice would she offer her younger self before she burst into the limelight?
“Oh gosh! It’s to stop being so stubborn because I was a very stubborn kid,” she laughed. “Very crazy too! I think it kind of halted a bit of stuff but I think it turned out for the best.”
She has quickly become a role model for a legion of young people, especially young women, not only for her prowess but also for her poise and personality.
So what advice would she give those who look up to her?
“Just to never give up and to write down your goals and to always wake up in the morning with something you love to do and that you have a passion for,” she said.