Adjust the chair height so that your hands are slightly below your shoulders. Similarly, for the rear delt fly, you can slightly change your posture depending on **where you want to focus more: the stretching phase of the rear shoulder or the contracting phase.** **How to focus on the contracting phase** As mentioned earlier, while sitting with your torso in a neutral position, proceed with the feeling of extending your hands diagonally forward. When you spread your arms, focus on maintaining the contraction feeling in the rear shoulder so that the tension does not shift to the trapezius. **How to focus on the stretching phase** Slightly round your torso.