Het spierstelsel

The muscular system includes the skeletal, smooth, and cardiac muscles that coordinate with each other to carry out functions like movement, digestion, and circulation.

Of the three muscle types, the skeletal muscles are the most predominant.

They form the musculoskeletal system, a complex network of muscles, bones, and associated connective tissues that produce voluntary movements, such as standing, walking, or running.

When a skeletal muscle contracts, it generates force to move one of the articulating bones while keeping the other relatively stationary.

Let's consider the example of the biceps brachii. Its two proximal ends called the origins, are attached to the scapula, a stationary bone.

In contrast, the distal end called the insertion, is attached to a movable bone, which is the radius in this case.

The muscle's origin and insertion are separated by a fleshy region called the belly or the gaster.

During elbow flexion, the origin of the bicep pins the muscle to the stationary bone,  supporting its insertion to pull the radius for movement.