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Medicine

What causes sudden muscle stiffness and pain?

Quick fact

Muscle cramps are sudden, involuntary contractions caused by overactive nerve impulses, often triggered by dehydration, electrolyte imbalance, or muscle fatigue.

Why this is interesting

A muscle cramp isn't just fatigue—it's a neurological misfire where your spinal cord sends hyperactive signals that override your muscles' ability to relax, locking them in a painful contraction.