Lie on your back on the floor (legs may be upright), hold the weights in front of your chest with your arms bent (elbows close to your body pointing forwards), grasp the dumbbells with a neutral grip so that your palms are facing the respective side, push the weights upwards to bring your almost fully extended arms to the holding position, then lower/bend your arms back to the starting position.
Attention:
Do not fully extend your arms in the holding position and do not place the weights completely on your chest when lowering them; keep your back in contact with the floor throughout the exercise.
Lighten:
Less weight.
Harden:
More weight.
Variant I:
Alternately push one arm up and lower it back to the starting position.
Variant II:
Press the dumbbells against each other during the entire exercise sequence.
Variant III:
Replace the dumbbells with a weight disc. Hold the weight disc with both hands at the edge (disc horizontal to the floor), or clamp the disc between your palms for additional strain on the chest muscles (disc horizontal to the floor).