When runner Allyson Felix heads to Tokyo to compete in the Olympics, she'll go as a six-time gold medalist, as well as a fierce champion of athlete mothers.

Felix called out her then-sponsor Nike in May 2019 for cutting her pay after the birth of her daughter, Camryn. Now she's advocating for child-care help for mothers as they train and compete for the Olympics and beyond.

"When I think about the world that Cammy will grow up in, I don't want her — or any other woman or girl — to have to fight the battles that I fought," Felix, 35, explained to CNBC in an email.

She's teamed up with her sponsor, Gap's Athleta, and Women's Sport Foundation to give out $200,000 in grants to professional mom-athletes traveling to competitions. The program recently announced the first nine recipients, six of whom are heading to Tokyo for the 2021 Games next week. They'll receive $10,000 each to use towards child care.

"It's really hard to balance being a mom and a professional athlete, and the reality is that there's a certain level of financial support and security that's necessary to be able to do it," Felix said.

Finding her voice

After she had her daughter in late 2018, she felt pressured to return to form as soon as possible, Felix wrote in the 2019 New York Times op-ed. Her contract with Nike had expired and the company wanted to pay her 70% less than her previous agreement, she said.

"There has always been a silence and a fear surrounding motherhood in sports," she recalled. "I remember feeling like I had to choose between this sport that I love and my family."

A short time after Felix spoke out, Nike changed its policy to guarantee that a pregnant athlete's pay can't be cut for 18 months, up from its 2018 policy of 12 months.

"We're always learning and growing in how to best support our female athletes," Nike said in a statement to CNBC.

"We're proud to have a strong roster of women athletes and Nike is committed to continuing to champion, celebrate and invest in them."

Felix, however, signed on with Athleta in July of 2019. Her new sponsor's support has made a real difference, including allowing Camryn to join her whenever she is competing, Felix said.

"The only way we'll see real change is if we all learn to raise our voices and ask for what we need," said Felix, who recently launched her own shoe brand, Saysh.

Lack of affordable child care

Other companies have also started paying more attention to child-care issues, particularly after the pandemic exposed the uneven burden on working mothers.

A survey earlier this year by McKinsey & Company highlighted the lack of affordable health care many working parents face. Of those who have incomes below $50,000 and children at home, only 39% said they could afford child care.

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On the public front, the Biden administration has pushed for an investment in child care, including federal funding to help low- and middle-income families afford high-quality care.

When it comes to Tokyo-bound Olympic athletes, they also face the additional burden of not being allowed to bring their children with them to Japan. The Games aren't allowing any international guests, but in June the organization made an exception for children being breastfed by their mothers.

That is why the $10,000 grant is a lifeline for volleyball player Lora Webster, who will be competing in the Paralympics. A mother of three, Webster does much of her training at home so she doesn't incur child-care costs. When she travels, she hires a hodge-podge of babysitters to cover her husband's workday.

Now she'll be able to fly family members in from Arizona and Italy to help out while she's in Tokyo. She's also looking into extended summer camps for her kids.

"This grant has not only given us financial assistance, but it has also given me the peace of mind to know that while I am halfway around the world, my family will have consistent and reliable help to get them through my absence," she said.

For Felix, the fight has just begun. As she's shared her experiences, she hears similar ones repeated back to her.

"It's also not just in sports — it's across the board," she said.

"There is still a really long way to go."

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