Garth Brooks Takes The Flex 4 Forces Challenge

(Radio.com) Ready to start flexing for a good cause? Join Garth Brooks and other celebrities to show your support for the armed forces through the United Service Organizations' #Flex4Forces campaign.

Since May 20, people from around the country have been snapping photos of their biceps and sharing their reasons for why they are participating. This social media campaign supports USO's mission to "strengthen service members by keeping them connected to family, home and country."

Brooks posted his own flexing photo from the gym earlier this week (May 30), calling out Ashton Kutcher and Brett Farve for their previous photos. He also tagged Serena Williams to post next.

He wrote, "Looking good @Favre4Official but @AplusK beats us both! I nominate @serenawilliams she's gonna show all of us boys up! love, g #Flex4Forces" Read more here.

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