[8] Felix, along with Alysia Montaño and Kara Goucher, is credited with stirring public outcry over Nike's refusal to guarantee salary protections for its pregnant athletes, prompting the sportswear brand to expand its maternity policy in 2019.

[11][12] In 2022, Felix received an honorary Doctor of Humane Letters degree from her alma mater USC and also served as the commencement speaker for that year's graduation ceremony.

A few months later, in front of 50,000 fans in Mexico City, she ran 22.11 seconds, the fastest in history for a high school girl, though it could not count as a world junior record because there was no drug testing at the meet.

[23][24] Felix graduated high school in 2003, making headlines by forgoing college eligibility to sign a professional contract with Adidas via her agent Nik Visger.

[31] At the 2007 Osaka World Championships, Felix caught Jamaican rival, Veronica Campbell, on the bend and surged down the straightaway to finish in 21.81 seconds, dipping under the 22-second barrier for the first time in her career.

Lauryn Williams, Felix, Muna Lee and Carmelita Jeter finished with a time of 41.58 seconds, bringing them to eighth on the all-time list.

In the 400-meter event, Felix's best efforts yielded only a second-place finish despite straining down the homestretch to a personal best of 49.59 seconds, 0.03 behind winner Amantle Montsho of Botswana.

Team USA won both events, attaining world-leading times in both finals as Felix added two world championship gold medals to her collection.

Felix pushed out of the blocks with a strong start and was on par with the Jamaican athletes coming off of the curve before pulling away in the final 50 meters to clinch her long-awaited individual Olympic gold medal.

Felix took to the track again as part of the women's 4 × 100 meters relay team alongside Tianna Madison, Bianca Knight, and Jeter.

After a nine-month layoff due to a hamstring injury, Felix resumed competition in the 400 meters at the Shanghai Diamond League meet in May 2014, in which she finished fifth with a time of 50.81 seconds.

She later competed in the 200 meters at the Prefontaine Classic meet, finishing third with a season's best of 22.44 seconds.As the winner of the 2014 IAAF Diamond League 200-meter title, Felix received a bye into the 2015 World Championships in Athletics.

Felix won the event in 50.19 seconds with a late surge from fourth place at the 300-meter mark, catching Natasha Hastings right before the finish line to earn her ninth U.S. championship title.

[52] Felix began her 2016 season with an uncharacteristically slow start after a gym accident in April, when she dropped from a pull-up bar and landed awkwardly, twisting her right ankle and tearing multiple ligaments.

[55] Felix took the rest of July and early part of August off to give her ankle more time to heal while she continued preparations for the Olympics.

The 4 × 100 meters relay win drew much controversy, as Team USA was initially disqualified in their semi-final run after Felix had dropped the baton during the handoff attempt to English Gardner.

However, replays showed that the Brazilian sprinter in the neighboring lane swung her arm and accidentally impeded Felix right before the handoff, causing her to lose her balance.

[61] Just a month prior to the championships, Felix had won the London's Diamond League meet held at the same track with a world-leading time of 49.65 seconds.

[66] During her 32nd-week pregnancy checkup, doctors discovered that Felix had developed pre-eclampsia, a condition that is disproportionately prevalent in African-American women and is marked by high blood pressure along with potentially harmful childbirth effects.

"[67] Felix furthered her maternal advocacy work in May 2019 by penning an op-ed for The New York Times, accusing her longtime sponsor Nike of refusing to guarantee salary protections for female athletes in the months following pregnancy.

[68] Her story underscored the earlier allegations made by her former Nike teammates Alysia Montaño and Kara Goucher regarding their pregnancy disputes with the sportswear company.

Planning to start a family in 2018, Felix asked Nike for written financial security, in case her performance yielded subpar results while recovering from childbirth; the negotiators declined after already offering a 70 percent pay cut in this contract proposal.

[9] In July 2019, Felix competed in her first race since giving birth in November 2018, finishing sixth in the 400-meter sprint at the U.S. national championships in Des Moines, Iowa.

Although failing to qualify into the individual 400-meter event for the 2019 Doha World Championships, Felix's sixth-place finish still placed her in the U.S. 4 × 400 meters relay pool.

She completed workouts on streets, empty soccer fields, and beaches after Gavin Newsom's quarantine measures were first enacted throughout California in March 2020.

[74][75] In June 2021, two years after she publicized her contract dispute with Nike, Felix launched her own footwear company, Saysh, and began wearing spikes created by the brand into competitions.

[80] Felix concluded her Olympic career after winning gold in the women's 4 × 400 meters final, alongside a team that included Sydney McLaughlin, Dalilah Muhammad, and Athing Mu.

[82] Allyson Felix is a five-time recipient of the Jesse Owens/Jackie Joyner Kersee Award, an accolade given by USA Track & Field to commend the chosen athlete of the year.

[93] As a councilmember, she appeared in short clips promoting healthy school breakfasts, mediated youth panels, and participated in a "Let's Move!

The program was designed to remove barriers and create activities that benefit audiences with and without disabilities, whilst speaking with a young, at-risk public about important life and sports values, such as respect, discipline and overcoming adversity.