You should have took the 45 and beat his fucking head in with it.
Then i would have pressed the fuck for 10 reps and said thank you it was the best chest workout i have had in ages!
second, wait till hes done working out and in the parking lot then hit him with your car, take his wallet, find his girl, tell her he's died in a tragic accident and that he sent you to console/bang her
Man takes me back to high school, at the very least you should have put some dog poop in his gym bag when he wasn't looking, or some contact cement on the bar