January 2021 | Reviewed by: Andrea Matsumura MD and Seema Khosla, MD
What are sleep leg cramps?
Sleep-related leg cramps are sudden and intense feelings of pain in the leg or foot. The pain is caused when a muscle contracts and tightens. The cramps occur without you being able to control them. They may happen while you are still awake or after you are asleep.
They normally begin very suddenly. Sometimes, they may begin slowly with less painful warning signs. The muscle cramps can last for a few seconds or several minutes. They end as suddenly as they began. They may occur as rarely as once per year in some people. Other people can have many cramps every night. In many people, the cramps tend to come and go over many years.
The cramps can be relieved by stretching the affected muscle. The muscle may still be tender and sore several hours after the cramp. At times, leg cramps can also be eased by the following:
- Massaging the area in pain
- Applying heat to the muscle
- Moving the affected leg or foot
The muscle cramp not only causes pain, but it can also disturb your sleep. It can make it hard for you to fall asleep. It may also wake you up after you have been asleep. The soreness felt after the cramp can also make it hard for you to go back to sleep again.
Leg cramps are sometimes confused with restless legs syndrome (RLS). Both problems involve discomfort with the legs during the time of sleep. RLS usually does not involve a feeling of pain nor does the muscle become tight. It also tends to be at least partly relieved as soon as there is any leg movement. This urge to move the legs is much stronger with RLS than with leg cramps. Relieving the pain from leg cramps involves more time and more stretching of the muscle. RLS also tends to occur in the evening hours while still and may prevent falling asleep. Sleep leg cramps tend to happen during sleep or around the time you go to sleep.