They are performing a maneuver called “squeeze army.” Basically to share solidarity with the football team during a critical play they squeeze their testicles to endure pain as a sign of support. http://pokerblog.blogspot.com/squeeze_ags.jpg
Someone needs to go back to Fish Camp.
For us 'non-regs' we were told it was called 'humping it'. Maybe the Corps had their own slang. I was never a quad-queen or boot chaser so I am not familiar with Corps slang.
btw, I would love to back to Fish Camp - had lots of fun and made some life long friends there!!!
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"I am the center of the universe!! I also like to chew on paper." my puppy