Shoulder and back, very annoying, like abdominal muscles. You should do more sit-ups and back lifts, preferably weight-bearing exercises, which are more effective in connecting back muscles. Shoulders, you should be more resistant to barbells. Multi-effect exercise also exercises your legs and waist. Let me introduce you to two methods that I think are more effective: 1. Take a barbell (weight of your choice), raise your hands, straighten them, and then move your hands back and forth without moving your forearms. 2. Pick up a barbell (the weight is also your choice), pick it up with both hands, without lifting it, and pull it up with your shoulders. draw
But the picture shows dumbbells, and dumbbell barbells can be used. That's all I know for now. There are coaches in the gym. You can ask them questions.
Dear, here you are. Play with your hands!