Question

During the quadruped t-spine rotation, what muscle is being engaged in the shoulder of the arm that's resting on the floor?

A) Rhomboids
B) Latissimus dorsi
C) Pectoralis major
D) Serratus anterior

Answer 1

During a quadruped t-spine rotation, the serratus anterior is the muscle engaged in the shoulder of the arm resting on the floor, as it helps position the pectoral girdle.

Step-by-step explanation:

The muscle being engaged in the shoulder of the arm that's resting on the floor during a quadruped t-spine rotation is the serratus anterior. This muscle is part of the anterior thoracic muscles and plays a key role in positioning the pectoral girdle. It is not the rhomboids, as they are posterior muscles that, when contracted, move the scapula medially and pull the shoulder and upper limb posteriorly. The muscles initially considered in the multiple-choice question include the rhomboids (A), which are not the primary muscles engaged during this movement. Therefore, the correct choice here is D) Serratus anterior.