This is one of the best moves to work your back, especially the large dorsal muscles and trapezoids.
This exercise was created by Vince Gironda and is very strict technical execution and a bit complex. The first thing to do before starting to perform this variation of rowing with dumbbells is to find a bench with sufficient height to allow the descent of the dumbbells up and down without them touching the ground at all.
Start the movement by taking the dumbbells with your arms straight down and knuckles pointing forward. From this position, pull the dumbbells up while keeping your elbows 90° to your trunk.
As the upper arms and elbows are aligned with the joints of the shoulders and the forearms are perfectly upright, arch up the head and legs from the bench surface and arching the back up so that belly just keeps in touch with the bench. At the same time tighten the shoulder blades up against one another.
It should be kept in this position for two seconds and then holding the weights in the maximum contraction position of movement. Return the dumbbells to the starting position and repeat the movement.