Dumbbell and barbell bench presses are very similar in terms of technique, and both engage the major shoulder muscle. However, the primary target of both is the pectoralis muscle in your chest. The difference is the barbell press works the upper chest, while the dumbbell press focuses on the lower chest.
Bench Press Technique
A barbell bench has a weight rack at one end. You'll have to reach up and take hold of the barbell from a lying position. Your hands must be just wider than your shoulders with your hands facing your feet. You'll start with the bar held over your chest with your arms extended. Lower it until it just about touches your chest, then extend your arms to push the bar back up.
Dumbbell Press Technique
Hold the dumbbells as you sit, then lie on your back on the bench. Begin with the dumbbells held just outside your torso at chest level. Your palms should face your feet, and your elbows should be directly in line underneath your wrists. Push the dumbbells over your chest until your arms are extended. Bring the weights together so they gently tap over the center of your chest, then lower them back to the starting position.
Barbell Bench Benefits
The barbell method is what you want if you're trying to build strength in your chest. It forces your muscles to lift a heavier load than they’re used to. A 2010 study published in the Journal of Sports Sciences found exercisers could lift a significantly higher load during a press exercise with a barbell compared to dumbbells.
Dumbbell Press Benefits
The Sport Journal study literally raised the bar when it came to dumbbell use. You won't hit your chest against one when you're exercising with dumbbells, which improves the range of motion in your shoulders. It also means your dominant arm can take on a greater percentage of the load.