Working
the main muscles of your chest, the flat bench dumbbell press gives an increased (deeper) range of motion (ROM) than when using a barbell (the barbell must always stop when it touches your chest), so can boost muscle growth even further.
Not exact matches
The
main benefit
of using dumbbells is that it requires you to engage a greater number
of muscles compared to the barbell and machine variant and actually activates the lower fibers
of the
chest press better than a barbell press — since your hands are free to move across your body when you use dumbbells, the lower pecs get a better workout.
The pec
muscle is comprised
of two
main portions: the upper clavicular fibers (otherwise referred to as the «upper
chest») and the lower sternocostal fibers.
This is why research shows that certain exercises, like the flat and decline bench press, emphasize the
main (large) portion
of the
chest muscle, whereas others, like the incline and reverse - grip bench press, emphasize the smaller upper portion.
The
main problem is that you're doing only one set
of one exercise for each major
muscle group — legs,
chest, back, shoulders, calves and abs.
In freestyle, the
main muscles used are the large
muscles of the thigh, and the
chest, back and shoulder
muscles.