43. Chin Ups
Chin ups are hard, but they're worth it. It's the twisting motion you generally have to use to hoist yourself up that makes them essential for getting rid of any muffin topping situations. In addition, you're building up serious strength in your arms, which will help you with many of the other exercises listed here. Now, I know chin ups can be really difficult, so you can modify them at first, and work your way up to the traditional technique.