Felix has nine Olympic medals in total
Six-time Olympic champion Allyson Felix has launched her own shoe brand in the build-up to this summer's Tokyo Games.
Felix said in 2019 that Nike wanted to pay her 70% less after she became a mother, before the company changed its contracts for pregnant athletes.
She later decided not to renew her contact and instead joined a women's athletic wear company.
"When it came to the Olympics this year I didn't have a sponsor for my racing spikes," Felix wrote on social media., external
"I was tired of asking for change. I knew I needed to create it."
Felix, 35, returned to the track two years ago after life-threatening complications arising from the birth of her daughter Camryn, who spent her first month in intensive care.
She took part in the United States trials for Tokyo 2020 and qualified for her fifth Games with a second-place finish in the 400m.
"When you see me run, know that I'm not running for medals," added Felix.
"I'm running for change. I'm running for greater equity for each of us. I'm running for women.
"More than anything, I'm running toward a future where no woman or girl is ever told to know her place."
A Life in Ten Pictures: The iconic images that proved defining for John Lennon
Do you know your football anthems?: Take the quiz that will put your knowledge to the test
