Muscle cramps especially in legs and hands occur due to various reasons:
1.
Poor blood circulation due to immobility/lack of adequate physical activity/confinement to bed. Reduced oxygen supply due to inadequate blood flow to muscles of legs and hands lead to cramps.
2.
Smoking or caffeine in tea, coffee or cola drinks also affect blood circulation.
3. Loss of potassium from body or inadequate intake of potassium rich foods.
4. Lack of calcium,
magnesium, sodium/potassium, chloride salts in the body
5. Inadequate fluid intake which may cause
dehydration.
Kindly mention your age, are you having any health issues like BP/circulation problems? are you on any medications as some medications can cause cramps as a side effect.
Also cramps occur after intense physical activity/exercise due to accumulation of lactic acid in the muscles. In such a case, cramps usually subside after a period of rest.
Are you under stress/ have you increased your physical activity of late like joining a gym etc.?
Do you venture out in the sun (tropical climate) often or do you sweat alot?
Kindly let me know more about your daily routine to find out the possible cause.