At first glance, there doesn't seem to be a lot of difference between a barbell and dumbbell incline press. After all, you're lying on a slanted bench and pressing weight above your chest. Both activate the fronts of the shoulders and the upper portion of the chest more than a flat bench press.
The two exercises round out a comprehensive chest training routine — but is there an advantage to using one piece of equipment over the other?
No Compensation with Dumbbells
In a barbell press, it's easy for your stronger side to compensate for the weaker side. Dumbbells mean each side of your chest, shoulders and triceps must work independently. Your weak side must step up and perform, meaning you'll get more even development with dumbbells.
More Power with a Barbell
If you want to move the most mass possible, a barbell is the right choice, showed a study published in the Journal of Sports Science in 2011. Researchers compared the one-rep maximum of participants using a barbell press and a dumbbell press. The max dumbbell lift weight was 17 percent lower than the barbell press. The more weight you can lift in a sitting, the more stress on your muscles. So, if your only goal is building size and strength, the barbell is then your best choice.
More Stabilization with Dumbbells
The 2011 study did demonstrate that the dumbbell press required a lot more stabilization work from your muscles than the barbell press. This means you'll develop more subtle functional muscle action with a dumbbell press and better core strength.
Incline bench racks are usually loaded with a standard or Olympic bar, which starts at 45 pounds. For the novice, this may just be too much weight. A dumbbell press allows you to start modestly, with a press of 8, 10 or 15 pounds.
As you progress to heavier dumbbells, however, they allow for less nuanced changes in weight than a barbell. You can add plates to a barbell in increments of about 2.5 pounds; most dumbbells go up in 5-pound increments. When you top out with a 30-pound dumbbell, for example, your only choice is to go up to 35-pound dumbbells in each hand — an increase of about 16 percent. If you use a barbell, a 60-pound bar (the equivalent of two 30-pound bells) can be increased to 65 pounds by adding a 2.5-pound plate to each side, which is a more reasonable 8 percent increase in weight.
The 2011 study further demonstrated that the dumbbell press and the barbell press elicited almost identical activation of the primary mover, the pec major, and the synergists — or helpers — the anterior delts and the triceps. You can't really go wrong with choosing one exercise over the other.
The Final Word
If you have uneven pec development, choose dumbbells to force your weaker side to buck up. Dumbbells may also be your choice if you usually use only the flat bench barbell press as your go-to exercise. Finishing your workout with an incline dumbbell press hits your muscles from a different angle and benefits your overall development.