Much like 2014’s Ice Bucket Challenge sought to promote awareness of ALS via social media, the USO’s #Flex4Forces campaign calls on Americans to show their strength by striking a biceps flex in support of our nation’s military and sharing it on social media.

Step 1: Show Your Strength

• Strike your flex pose
• Snap a picture or record a video explaining why you are flexing

Step 2: Share on Social

• Tag the USO and use #Flex4Forces
• Nominate four people to flex next
• Start sharing social posts on Armed Forces Day, May 20

Country stars Tim McGraw, Garth Brooks and Phil Vassar have gotten into the spirit of the campaign. Check out the guys flexing their guns.

I was nominated by @RobertIrvine to #Flex4Forces with @the_USO… I nominate @Favre4Official and @SollyThomas90 pic.twitter.com/zlGK8QfV5s

— Tim McGraw (@TheTimMcGraw) May 28, 2017

Looking good @Favre4Official but @AplusK beats us both! I nominate @serenawilliams she’s gonna show all of us boys up! love, g #Flex4Forces pic.twitter.com/ZMVJOBgTmj

— Garth Brooks (@garthbrooks) May 30, 2017

15% of @philvassar new album supports our servicemen and women of @the_USO ! Show your strength and #Flex4Forces https://t.co/DFphpsg7s9 pic.twitter.com/YVj4dW7ENi

— FOX & friends (@foxandfriends) May 26, 2017