Sit on your back on the flat bench in a negative position, i.e. pointing downwards (decline) (head closer to the floor than the legs). Hold the weights with bent arms (approx. 90 degrees at the elbow joint) slightly above chest height (with the upper arms pointing to the respective side), grasp the dumbbells with a pronated grip so that the palms are facing forwards, push the weights upwards to bring the almost fully extended arms into the holding position, then lower/bend the arms back to the starting position.
Attention:
Do not fully extend your arms in the holding position and do not bring the weights fully together.
Lighten:
Less weight.
Harden:
More weight.
Variant I:
Alternately push one arm up and lower it back to the starting position.
Variant II:
Bench in a straight/flat position (flat bench) or in an inclined position with the seat facing upwards at an angle (incline).