It’s one of the simplest and oldest pieces of equipment—the humble dumbbell. And while we're all familiar with the go-to moves like your basic bicep curl or tricep extension, a pair of dumbbells is good for more than a few arm exercises. The weights can actually provide a full-body workout in a compact amount of space that will shred unwanted fat, sculpt muscle and strengthen your core. Herewith, four essential moves to master. As for the amount of repetitions or sets, we'll let you determine that for yourself based on your personal fitness goals.