Wieber was a member of the gold medal-winning U.S. Women's Gymnastics team, self-dubbed the "Fierce Five", at the 2012 Summer Olympics.

She was also a member of the gold-winning American team at the 2011 World Championships, where she also won the individual all-around title and was the bronze medalist on the balance beam.

My parents noticed that I had unusually bigger muscles than a typical little kid, so they put me in gymnastics.

[6] Wieber rose to the Junior International Elite level in 2006, at age 11, where she placed ninth in the all-around at the 2006 National Championships.

[10] In 2007 Wieber competed at the U.S. Classic where she placed fifth in the all-around but won silver on balance beam and vault.

[11] At the 2007 National Championships Wieber won bronze in the all-around behind Rebecca Bross and Samantha Shapiro.

[12] Wieber was later named to the team to compete at the 2007 Junior Pan American Championships alongside Olivia Courtney, Mattie Larson, and Chelsea Davis.

[17] Wieber was named to the team to compete at the 2008 Pacific Rim Championships but had to withdraw due to injury.

She also placed first on vault and floor exercise, second on balance beam, and third on uneven bars.

[21] Later that year in March Wieber competed at International Gymnix where she helped the team win gold and individually she placed first in the all-around and on all four apparatuses.

[23] In April 2010, was named to the team to compete at the 2010 Pacific Rim Gymnastics Championships in Melbourne, Australia alongside seniors Aly Raisman, Rebecca Bross, and Bridget Sloan and fellow juniors Kyla Ross and Sabrina Vega.

[25] Individually, she won the all-around competition with a score of 59.550, finishing ahead of Ross, Vega, and Russian Anna Rodionova.

[28] She also won gold on vault and uneven bars, silver on floor exercise behind Katelyn Ohashi, and placed sixth on balance beam.

[29] In August, Wieber attended the National Championships but sprained her ankle on the balance beam and withdrew from competition.

[30] In March, Wieber participated in her first senior elite competition at the American Cup in Jacksonville, Florida, where she filled in for an injured athlete.

She placed first on uneven bars with a score of 15.200 and tied for first on balance beam with Olympic medalist Alicia Sacramone.

"[38] In October, Wieber competed at the 2011 World Artistic Gymnastics Championships in Tokyo, Japan.

[40] Wieber was a finalist for the James E. Sullivan Award, which is given annually by the Amateur Athletic Union.

"[44] Later in March, Wieber competed at the 2012 Pacific Rim Gymnastics Championships in Everett, Washington.

"[52] In early July, Wieber competed at the Olympic Trials in San Jose, California.

This marked the first time an entire Olympic gymnastics team had been featured on the cover of "Sports Illustrated".

[57] At the end of July, Wieber competed at the 2012 Summer Olympics in London, United Kingdom.

In qualifications, she placed fourth overall with a score of 60.032 behind teammates Aly Raisman and Gabby Douglas, meaning that she would not advance to the all-around final due to the rule limiting participating countries to having a maximum of two competitors in the all-around final.

"[67] After the Olympics, Wieber announced that she had been competing with a stress fracture in her right leg caused by a heel injury.

During her senior year of college, Wieber became a volunteer assistant coach at UCLA for the 2016–17 season.

She served as the floor exercise coach for the Bruins, helping them finish the 2018 and 2019 regular seasons ranked number 1 on the event.

[81] They married on May 28, 2023, with a guest list including Wieber's Fierce Five teammates Aly Raisman and Kyla Ross.

[82] On January 19, 2018, Wieber testified in court that she was sexually abused by the long-term team doctor of USA Gymnastics, Larry Nassar.