In short
A night leg cramp is a sudden, painful tightening of a muscle, usually in the calf or foot. To stop one, stretch the muscle by pulling your toes towards your shin or standing on the leg. Most cramps have no serious cause. Stretching before bed may reduce them. Magnesium probably doesn’t, except possibly in pregnancy.
On this page
What are night leg cramps?
A night leg cramp is a sudden, involuntary and painful contraction of a muscle while you are resting or asleep. The calf is the usual place, followed by the foot and thigh. The muscle goes hard, the pain lasts from seconds to several minutes, and the area can stay tender into the next day.6
They are common, particularly later in life. In a study of patients over 60 seeing a GP, almost half reported cramps, and about one in three had been woken by them.1
How to stop a leg cramp immediately
- Stretch the cramping muscle. For a calf cramp, straighten your leg and pull your toes and the ball of your foot up towards your shin. Hold until it eases
- Stand up and put your weight on the leg, pressing your heel into the floor
- Walk around for a minute or two
- Massage the muscle, and use a warm pack or warm shower to help it relax afterwards
Stretching the muscle is the quickest way to end a cramp.6
Sleep still not right?
Talk it through with an Australian doctor online. No referral needed.
What causes leg cramps at night?
For most people no single cause is found. Cramps are more likely with:6
- Getting older
- Pregnancy, especially the later months
- Unusually hard exercise, or long periods of standing
- Sitting or lying with the foot pointed for long periods
- Dehydration, heavy sweating or low salt levels
- Some medicines, including fluid tablets and some medicines for cholesterol, asthma and blood pressure
- Medical conditions that affect nerves, circulation or the body’s salt balance, such as diabetes, kidney disease, thyroid problems and narrowed leg arteries
Leg cramps or restless legs?
They are easy to confuse because both strike at night. A cramp is painful, the muscle is visibly or palpably tight, and stretching ends it. Restless legs syndrome is an urge to move, without a hard muscle, that returns as soon as you stop moving.7
Does stretching prevent night cramps?
It may. In a randomised trial of older adults, six weeks of calf and hamstring stretches done just before bed reduced cramps by about one a night more than in the group who didn’t stretch, and made them less painful.3
A Cochrane review was more cautious. It concluded that daily calf and hamstring stretching may reduce how severe night cramps are, that the effect on how often they happen is uncertain, and that the evidence overall is low quality.2
Stretching is free and safe, so it is the sensible first step. A simple routine: stand facing a wall an arm’s length away, lean in with your heels on the floor until you feel the stretch in your calves, hold for ten seconds, and repeat a few times.
Does magnesium help leg cramps?
Probably not. A Cochrane review of the trials concluded that magnesium is unlikely to give meaningful relief from cramps in older adults. For cramps in pregnancy the trials conflict.4 A separate review of treatments for leg cramps in pregnancy, including magnesium, calcium and vitamins, found it was unclear whether any of them work.5
If you want to try magnesium, see magnesium for sleep for safe doses, and talk to your doctor or midwife first if you are pregnant.
Other things worth trying
- Drink enough through the day, particularly in hot weather or after exercise
- Keep bedclothes loose at the foot of the bed so your feet aren’t pushed into a pointed position
- Stay active through the day
- Ask your doctor or pharmacist whether any of your regular medicines could be contributing. Don’t stop a prescribed medicine without advice6
When to see a doctor
- Cramps are frequent, severe or regularly disturbing your sleep
- Cramps began after starting a new medicine
- You also have muscle weakness, numbness or wasting
- Calf pain comes on with walking and eases with rest
Seek urgent care for a calf that is swollen, red, warm and painful and doesn’t ease with stretching. That can be a blood clot, not a cramp.
Next step: talk to a doctor
Answer a few quick questions and you’ll get an email about your eligibility. A consultation doesn’t guarantee any particular treatment.
References
- Maisonneuve H, Chambe J, Delacour C, et al. Prevalence of cramps in patients over the age of 60 in primary care : a cross sectional study. BMC Fam Pract. 2016;17(1):111.
- Hawke F, Sadler SG, Katzberg HD, et al. Non-drug therapies for the secondary prevention of lower limb muscle cramps. Cochrane Database Syst Rev. 2021;5(5):CD008496.
- Hallegraeff JM, van der Schans CP, de Ruiter R, et al. Stretching before sleep reduces the frequency and severity of nocturnal leg cramps in older adults: a randomised trial. J Physiother. 2012;58(1):17-22.
- Garrison SR, Korownyk CS, Kolber MR, et al. Magnesium for skeletal muscle cramps. Cochrane Database Syst Rev. 2020;9(9):CD009402.
- Luo L, Zhou K, Zhang J, et al. Interventions for leg cramps in pregnancy. Cochrane Database Syst Rev. 2020;12(12):CD010655.
- Better Health Channel (Victorian Government). Muscle cramp.
- Allen RP, Picchietti DL, Garcia-Borreguero D, et al. Restless legs syndrome/Willis-Ekbom disease diagnostic criteria: updated International Restless Legs Syndrome Study Group (IRLSSG) consensus criteria--history, rationale, description, and significance. Sleep Med. 2014;15(8):860-73.
This guide is general information, not medical advice. It doesn’t replace a consultation with a doctor who knows your history. In an emergency, call 000.