To put on a condom.

The term was originally used in reference to being "all-in" on Tampa Bay Buccaneers running back Doug Martin, who is known as the muscle hamster. However, the term sounds much more like putting on a condom.
"You don't know where that chick has been. Better hang your hat on the muscle hamster."
by JohnRambo10 August 31, 2014
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