Almost all of us have experienced a painful tightening of the calf muscles, which is called a cramp. Also called charley horses, these unpleasant experiences often come about during exercise, but can also happen as a result of venous disease and other health conditions. Leg cramping can also occur at night for the same reasons.

What causes leg cramping?

Some scientists hypothesize that modern lifestyle may contribute to leg cramping. Our early ancestors probably engaged in repetitive squatting, which stretches the leg tendons and muscles. Humans today simply don’t stretch their leg muscles as much, since we aren’t as active.

Other research suggests that leg cramping comes from some kind of nerve dysfunction. Muscle fatigue is often behind leg cramping as well, as many exercise enthusiasts and athletes know full well.

Vein related cramping

Vascular disease is commonly associated with leg cramping as well. One study showed that 75 percent of people with peripheral vascular disease reported leg cramps. Venous insufficiency has been tied to leg cramps. Pregnancy has long been associated with leg cramping, and this may be because of venous insufficiency that can occur during pregnancy.

Veins transport blood that is low in oxygen and high in waste products back to the heart and organs, so that the blood can be replenished. If vein valves aren’t functioning properly, as is the case with venous reflux disease, blood can pool in the legs. This can be a contributing factor of leg cramping.

Even if you don’t have visible varicose or spider veins, you may still be suffering from venous disease. Watch for symptoms like aching legs, cramping, skin color changes and swelling.

Nocturnal Leg Cramps

About half of all adults have experienced nocturnal leg cramps, which can be caused by vascular disease. Nocturnal leg cramps are slightly more common in women, and prevalence increases with age. Disrupted sleep is tied to a number of other health conditions, so it is important to find a resolution quickly.

Leg Pain That Isn’t Cramping

Venous insufficiency and venous disease can lead to leg pain that may be mistaken for leg cramping. Leg cramps can be recognized in this way: you’ll feel the muscle contract, but then not relax. Vein issues can lead to leg heaviness, fatigue and discomfort, and should be treated.