ACSM Personal Trainer Certification Practice Exam

What action does the pronator teres perform at the wrist joint?

1. Supination

2. Extension

3. Flexion

4. Pronation

The correct answer is: Pronation

The pronator teres primarily functions to facilitate pronation of the forearm. Pronating the forearm means rotating the radius over the ulna, which results in the palm facing downward or backward. This muscle is located in the superficial layer of the anterior forearm and arises from the medial epicondyle of the humerus. When it contracts, it pulls on the radius, inducing this rotational movement. This function is essential in various daily activities that involve forearm rotation, such as turning a doorknob or reaching for an object. While the term "wrist joint" is used in the context of this question, it's important to recognize that the pronator teres influences the position of the forearm rather than movements specifically at the wrist itself.