Heres my advice on what you should do with the equipment you have.
Use the barbell to throw through the window of a gym(after hours). Use the bench to step on(if needed) to get through the broken glass of the window of the gym. Use one of the dumbbells to hit the security guard over the head. Use the other dumbbell if he decides to get up.
Steal as much equipment from the gym that will fit into your already stolen truck/van. Don't use a white windowless V.Basile type van. Cops are always on the look out for those types of vans. And steal some tags. Maybe even from an old villian of yours.
If the police catch up to you while driving, slow down and let them pull up to the side of the stolen truck or van. Then, use your assorted weight plates to throw like frisbees at any and all police cars. If done right, you should be able to cause them to wipe out. You might want to practice throwing weight plates just to be sure though.
I would also advice you to wear some sort of mask when doing this. Any past American Presidents masks would be a good touch. Maybe even throw a surfboard on the top of the van/truck just for giggles.
And if by any chance you do get busted by Johnny Utah. Just tell him your name is Bodhi and your trying to get in shape so you can surf a once in a lifetime fifty year storm. He'll probably uncuff you and just let you go.
Hint: Its dangerous to jump out of a perfectly good airplane.