Maybe people have a hard time thinking of butterflies when they're getting their pump on, because somewhere along the line, dumbbell butterflies became just plain old dumbbell flyes.

Like an old-school barbell bench press, flyes are done from a lying position and work many of the same muscle groups, like the pecs, deltoids, triceps and biceps.Whether you've got dumbbells or a machine, you've got options for making your pecs float like a fly and sting like a bee.

Perform Classic Dumbbell Flyes

Perform a classic dumbbell fly by grabbing a dumbbell in each hand. Lie with your back flat on a bench. Hold your arms straight up so that the dumbbells meet, with your palms facing each other and the weights roughly in line with your sternum. Your feet should stay flat on the floor or pad.

Driving the movement by pulling your shoulder blades down and back, inhale and lower the dumbbells to your sides with your arms outstretched so that your elbows are just slightly bent. Now exhale as you return to the starting position, keeping your head, butt and shoulders flat throughout — think of it as sort of a hugging move as you feel the muscles of your chest press together.

Just as with a bench press, adjusting your bench to about a 45-degree incline or decline affects your muscle engagement. For more emphasis on the upper pecs (the clavicular head of the pectoralis major), go with an incline. To target the middle or lower pecs (the sternal heads) use a declined bench.

Machine Flyes

If someone at the gym is throwing around the term "butterfly presses," there's a good chance they're talking about workout also known as the lever pec deck fly. This one mimics the arc-like movement of the lying dumbbell chest fly, but has you seated at a lever machine.

How To: Keep your back flat on the pad as you take a seat on the machine, with your knees at about 90 degrees, toes pointing forward and feet flat on the floor. Place your forearms on the lever's pads, grasping the handles with an overhand grip, forming another 90-degree angle at your elbows and forearms.

With a smooth, controlled motion, push the two levers together as you exhale. Inhale as you return to the starting position, feeling that satisfying stretch in your chest.

Like a dumbbell fly, the pec deck works the clavicular and sternal pecs. It doesn't engage your biceps, triceps or wrist flexors like its bench-based brother, but it does stimulate the serratus anterior muscles located on your upper ribcage. On the plus side, it's a wholly chest-targeting workout that's easily accessible and doesn't require a spotter, even if you're lifting heavy weights.