In a first-class lever system, which components act on opposite sides of the fulcrum?

In a first-class lever system, the components that act on opposite sides of the fulcrum are indeed the muscle and resistive forces. In this type of lever system, the fulcrum is positioned between the applied force (muscle) and the load (resistive forces such as gravity or weight being lifted).

When the muscle contracts, it applies force to one side of the fulcrum, allowing for movement or overcoming resistive forces on the other side. This is a fundamental principle in biomechanics that demonstrates how muscles produce movement by leveraging their strength against resistive forces, which can include body weight or external weights.

Understanding this concept is crucial for analyzing movement patterns and maximizing the efficiency of exercises and athletic performance, as first-class levers are commonly found in many body movements, such as during the action of the triceps during elbow extension.