The semispinalis thoracis muscle is a deep muscle in the back that supports movement from the neck to the waist.

The multifidus thoracis muscle is a part of the back muscles, mainly involved in stabilizing the spine.

He started exercises to strengthen his sternocleidomastoid muscle.

This ancient proverb, 'know the other side and yourself, and you will not be in danger in a hundred battles', teaches us the importance of understanding ourselves and others.