There are numerous reasons why your legs are cramping at night, some of which are preventable and some of which may be telling you that there is an underlying condition that needs your attention. Any time that your leg severely cramps, you may have residual soreness for several days because your muscle been been unnaturally bunched up into a tight ball until the cramping subsided.
A nighttime leg cramp can be so excruciating that not only does it bring you out of bed with a yelp but the aftermath of the cramp can linger and cause muscle soreness in your leg, according to Healthline.com (see Resources). A severe leg cramp can result in persistent swelling and soreness in the affected muscle up to several days after the cramp has subsided, according to Medicinenet.com (see Resources).
According to Diabetichealthinfo.com, water pills (diuretics) help the body get rid of salt (sodium) and water, which forces the kidneys to put more sodium into your urine. When this happens, the sodium leeches water from your blood and this decreases the levels of fluid in your blood vessels, which reduces the pressure on the walls of your arteries. This is good for someone who has too much fluid in his body and needs to get rid of it; however, diuretics can deplete potassium levels in your body and this can lead to nighttime leg cramps. The Diabetes Information Library explains that individuals who have diabetes, and who take insulin as a result, may suffer from low potassium levels and that is why they are experiencing cramps in their legs. Deficits in sodium and magnesium can occur in people who have diabetes, which also causes leg cramps.
Nocturnal leg cramps can be caused by inactivity during the day, according to Wellsphere.com. Inactivity not only means absence of exercise but that you are walking wrong, which results in limited mobility at the muscle joint, which can cause you to cramp at night. Nighttime cramping can also be caused by dehydration, which can result in a fluid imbalance.
Some people vow that eating bananas regularly, which introduces potassium into the body, will eliminate sore leg muscles and leg cramps. It is believed that a deficiency in potassium can lead to cramping and soreness, according to Dummies.com.
Although the medical community isn't quite sure why this is so, if you have a deficiency in B6 (pyridoxine), B5 (pantothenic acid) or B1 (thiamine), this can lead to cramping.
Chronic ischemia is one of the major reasons behind leg cramping, according to Cure-back-pain.org (see Resources). When blood flow is restricted, oxygen deprivation occurs in parts of the body and this can cause pain and cramping. Blood clots, heart problems and clogged arteries (atherosclerosis) can result in nighttime leg cramps. Circulation to the legs can be reduced during sleep and severe cramps can occur. This is called claudification pain. According to Medicinenet.com, this pain is actually not a typical cramp, although it feels like one, but rather the result of lactic acid and other chemicals accumulating in the muscles.
If you are heavily pregnant, you may experience leg cramps at night because your legs are getting a workout during the day, carrying around that extra load, and also because the enlarged uterus may be resting on body parts that aren't used to this additional pressure. Other conditions such as peripheral artery disease (PAD), an under-active thyroid (hypothyroidsim) and Addison's disease can cause nighttime leg cramping.