Nocturnal leg cramps are sudden, involuntary contractions of the leg muscles, typically affecting the calf, that occur during sleep. These cramps can vary in intensity, lasting from a few seconds to several minutes, and may leave the muscle tender afterward.
While they can affect anyone, certain factors increase their likelihood:
Dehydration

Inadequate fluid intake can lead to an imbalance of electrolytes—such as sodium, potassium, and magnesium—that are vital for muscle function. This imbalance can trigger muscle cramps during the night.
Mineral Deficiencies

Deficiencies in essential minerals like potassium, calcium, and magnesium can contribute to muscle cramps. Ensuring a balanced diet rich in these nutrients supports proper muscle function.
Overexertion and Muscle Fatigue

Engaging in intense physical activity, especially without adequate warm-up or cool-down, can lead to muscle fatigue and subsequent cramping during rest periods.
Prolonged Sitting or Standing

