A jobby is Scottish for taking a shit.
Gym jobby, is the sudden and dramatic onset of the urge to evacuate the bowel during or post exercise. It's usually outside of your normal shitting routine and down to a combination of diet and literally busting your ass at the gym.
Where did Jim go? He's mean to be spotting me on the weight bench!

He ran to the toilet pretty quick, I think he needed a gymjobby!
by Donreevie January 21, 2018
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