dumbbell lying one arm deltoid rear

How to do this exercise

1. Step:1 Lie face down on a flat bench with a dumbbell in one hand, palm facing inwards.
2. Step:2 Extend your arm straight down towards the floor, keeping it close to your body.
3. Step:3 Raise your arm up and back, squeezing your shoulder blade towards your spine.
4. Step:4 Pause for a moment at the top, then slowly lower your arm back down to the starting position.
5. Step:5 Repeat for the desired number of repetitions, then switch arms.