010-111 · Question #2
What action is involved in the concentric phase of the biceps curl?
The correct answer is A. Flexion at the elbow. The concentric phase of a muscle contraction is when the muscle shortens, producing the primary joint movement. In a biceps curl, this is elbow flexion during the upward lifting phase.
Question
What action is involved in the concentric phase of the biceps curl?
Options
- AFlexion at the elbow.
- BExtension at the elbow.
- CPronation of the forearm.
- DSupination of the forearm.
How the community answered
(43 responses)- A84% (36)
- B2% (1)
- C5% (2)
- D9% (4)
Why each option
The concentric phase of a muscle contraction is when the muscle shortens, producing the primary joint movement. In a biceps curl, this is elbow flexion during the upward lifting phase.
During the concentric phase the biceps brachii shortens under tension, pulling the forearm upward and producing flexion at the elbow joint. This is the 'lifting' portion of the curl where the muscle generates force to overcome gravity and move the load toward the shoulder.
Elbow extension occurs during the eccentric (lowering) phase of the curl, when the biceps lengthens under load to control the descent of the weight.
Pronation is a rotational movement of the forearm turning the palm downward and is not the primary joint action produced by the biceps during the concentric phase.
Supination is a forearm rotation movement and, while the biceps assists supination, it is not the defining joint action of the concentric phase of the biceps curl.
Concept tested: Concentric muscle contraction and elbow joint action
Topics
Community Discussion
No community discussion yet for this question.