Final answer:
In a curl, the movement of bending the arm and bringing the weight closer to the shoulder is known as flexion, which is an angular movement that decreases the angle between the bones of the joint.
Step-by-step explanation:
The type of movement in which the bodybuilder bends their arm to bring the weight closer to their shoulder is flexion.
Flexion is a type of angular movement where the angle between the bones of a joint decreases. When a bodybuilder performs a curl, they are actively engaging their biceps to move the forearm upwards towards the shoulder. This exercise decreases the angle between the forearm and the upper arm, which is encompassed by the action of flexion. Conversely, the action of extension occurs when the muscles contract to increase the angle between bones, thereby straightening the joint. An example of extension is when the triceps brachii contracts to straighten the arm after it has been flexed. Moreover, other types of angular movements include abduction, where a limb moves away from the midline of the body, and adduction, where it moves towards the midline. The described movement in the question, however, pertains to the action of flexion, which is integral to many exercises focusing on the biceps, such as the bicep curl.