Why an earthworm loses its cylindrical shape when it dies?

When an earthworm dies, its muscles relax, causing the body to lose its cylindrical shape. Normally, the worm's body is maintained in a specific form by the tension in its muscles and the presence of coelomic fluid. Upon death, the loss of muscle tone and the inability to maintain internal pressure result in the worm's body becoming limp and flattened. This change is a natural consequence of the cessation of biological functions.