It is said that your weight and height are suitable, not too thin or fat. If you feel that your shoulders are narrow, it is either your personal feeling (in fact, it is not narrow) or you belong to a small skeleton!

The following is an excerpt from a friend's answer, combined with his own experience, I hope it will be useful to you!

The plan is to train for one day, rest for one or two days after three days, and then repeat!

Exercise box

Flat barbell bench press 3 groups-10 times (training the whole chest)

Lower inclined plate barbell bench press 3 groups-10 times (training lower chest muscles)

Parallel bars arm flexion and extension (wide grip) 2 groups-10 times (training lower chest muscles)

Upper flat dumbbell press (30-degree angle) 3 groups-10 times (training upper chest muscles)

Three groups of flat dumbbell flying birds-10 times (training chest muscles)

Three groups of instruments clamped chest-10 times (training thoracic sulcus)

shoulder

Sit on the barbell and press 3 groups-10 times (all shoulders)

Press the dumbbell for 3 groups-10 times (all shoulders)

Vertical barbell pull-ups (narrow grip) 3 groups-10 times (deltoid anterior middle bundle muscle)

3 groups of dumbbell side lifts-10 times (deltoid anterior middle bundle muscle)

3 groups of chest clamping in reverse sitting position-10 times (deltoid posterior bundle muscle)

Dumbbell prone bird group 3-10 (deltoid posterior bundle) triceps brachii

Narrow grip bench press 4 groups-10 times

Supine arm flexion and extension 3 groups-10 times (triceps brachii)

Press the instrument for 3 groups-10 times (triceps brachii)

Standing dumbbell lift 3 groups-10 times (triceps brachii)

biceps brachii

Barbell bending 3 groups-10 times (biceps brachii)

Three groups of dumbbell bends-10 times

Bracket bending for 3 groups-10 times (biceps brachii)