Brief Answer:
Can be due to electrolyte disturbance.

Detailed Answer:
Hello,
Thanks for posting your query.
Muscle cramps most of the time occur for no known reason, and they're harmless.

Sometimes, it can be due to dehydration, muscle fatigue or electrolyte abnormalities. It is better to drink sufficient fluid and also see that your intake of electrolytes (sodium, potassium, magnesium ) is sufficient. You can drink Oralyte for this.
Most cramps can be stopped if the muscle can be stretched. For many cramps of the feet and legs, this stretching can often be accomplished by standing up and walking around. Gently massaging the muscle will often help it to relax, as will applying warmth from a heating pad or hot soak. If the cramp is associated with fluid loss, as is often the case with vigorous physical activity, fluid and electrolyte (especially sodium and potassium) replacement is essential. Certain drugs like baclofen are helpful.

I hope this answers your query.
In case you have additional questions or doubts, you can forward them to me, and I shall be glad to help you out.
Wishing you good health.
Regards.
Dr. Praveen Tayal.
For future query, you can directly approach me through my profile URL http://bit.ly/Dr-Praveen-Tayal

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