This exercise is for your brachioradial muscles. It can be performed in a sitting or a standing position.
Stand up straight, grasp the dumbbells with palms facing your torso.
Slightly bend your elbows.
From the starting position lift the dumbbells up slowly without moving or swinging your body.
Pause for 1-2 seconds at the top, then slowly return to the starting position as you inhale.
If the weight is too heavy, you will also use your back and legs, that shifts the load to the waist.
Do not use a weight belt - you should keep your back straight by contracting the muscles of your back and abdomen.
You can lift both hands together or alternatively.