In order to avoid injuries of the upper and middle spine, it is very important to avoid spine flexing.
- Sit with a straight back in this exercise.
- Lean your chest on the pillow in front. it's ok if you torso will behind your chest, while the spine is straight and chest is fixed.
- Control shoulders movement and avoid helping yourself by moving the spine.
To do this, raise your chest up and set head back, it may feel uncomfortable if your muscles not used to the right posture.
- Squeeze your back, this and Body tilt will push your head forward, fight this as long as you can and if you feel your head falling front, stop the exercise even if delts have move reps in stock.
To feel what we trying to avoid during the exercise, raise your chest up and down (bad - don't do it) now you know what we don't want.
Your back is a lot stronger than rear delts always start lighter and proper form to find the best weight.