Nick Symmonds, an American middistance runner, won't be competing in the world championships in Beijing this month.

Symmonds, who is a U.S. National champion and has competed in the Olympic Games, failed to sign a terms and conditions agreement with USA Track & Field that is necessary to be part of the team. He has a personal sponsorship deal with Brooks Running, while the American world championships team is sponsored by Nike.

He posted this photo of the USATF letter he received to his Instagram account:

After receiving the letter that said he had to wear either Nike or nonbranded apparel, Symmonds posted again on his Instagram, asking that the team contract be rewritten, because he wouldn't sign it with the sponsorship requirements.

Because he wouldn't agree to wear Nike, the team replaced him, writes ESPN:

" 'Two years' worth of work to try to win another medal for my country are now down the drain,' Symmonds said. 'Is it frustrating? Of course. But no part of me regrets doing this.'

"Symmonds decided to take a stand in order to push for more rights for his fellow athletes, believing they should be rewarded with a bigger piece of the pie."

USATF said that it respects his decision but that the Statement of Conditions has been in place for years and that "athletes and agents are familiar with the provisions of the document, which include requirements pertaining to athlete conduct as goodwill ambassadors for the United States, proper handling of the American flag, wearing the designated Team uniform at official Team functions, attendance at official Team practices, meetings and other events, commitment to train and report fit to compete, and following doping rules."

It adds that it has no restrictions on "athlete footwear, eyewear or watches."

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