Final answer:
In kyphosis and depressed chest, the muscles in the thoracic region, such as the rhomboids, may be tight. Other muscles that may be affected include the trapezius, levator scapulae, and serratus anterior.
Step-by-step explanation:
In kyphosis and depressed chest, the muscles in the thoracic region are often tight. One of the main muscles affected is the rhomboid muscles, which are located on the posterior thorax. When these muscles contract, they move the scapula medially, pulling the shoulder and upper limb posteriorly. Other muscles that may be tight in kyphosis and depressed chest include the trapezius, levator scapulae, and serratus anterior.