The dumbbell rollover is a great supplemental movement for the bench press because it increases tricep strength substantially. You'll lift the weight like you would when doing a triceps extension, but lower the weight as you would a bench press.
Be sure to keep the elbows in line with the shoulder and don't allow them to travel forward during the extension portion of the movement.
Do this exercises in 2-3 week cycles with dumbbells that are challenging enough to perform 2-4 sets of 6-10 reps for strength, or 12-20 reps for massive tricep growth.
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