In a standard biceps curl, which class lever is formed at the elbow?

• A. Fourth-class lever
• B. Second-class lever
• C. First-class lever
• D. Third-class lever

Answer: (D)

The elbow curl uses the elbow as the pivot point, with the resistance at the hand located far from that pivot and the muscle pulling on the forearm between the elbow and the hand. This arrangement—effort between the pivot and the load—defines a third-class lever. It gives you a greater speed and range of motion at the hand, but it requires greater muscular force to move the same weight compared with other lever types. In contrast, a seesaw has the effort and load on opposite sides of the pivot (first-class), and a wheelbarrow has the load between the pivot and the effort (second-class). A fourth-class lever arrangement isn’t how the elbow curl is set up, so it isn’t the correct model here.