The most effective way to exercise back muscles is pull-ups.
How to train the long head of biceps brachii for better results
Good shoulder training moves: Alternate front and back barbell presses!
ytwl video: ytwl shoulder training instruction
What is the best way for men to lose weight on their belly?
[Side Lunge] Mainly exercises the inner thigh muscles
Simple and practical back training program
Several butt and hip training exercises for both men and women
Reverse Fly Technique: Externally Rotate Your Shoulders!
Detailed explanation of serratus anterior muscle training methods for women