Muscle Cramps

What is a muscle cramp?

A muscle cramp happens when a muscle in the body tenses or stiffens up. Cramps are involuntary, which means your child cannot control them. A cramp comes on suddenly, without warning, and causes pain or discomfort. Your child may not be able to use the affected muscles for a short time.

Signs and symptoms of muscle cramps

  • sharp muscle pain

  • sudden muscle spasm, which is like a sudden seizure or twinge

  • tightening of muscles, often in the legs

  • a visible hard lump of muscle beneath the skin

  • cramps that occur in your child’s calf muscles or toes during sleep

Causes of muscle cramps

Many things can cause a muscle cramp. Children often get muscle cramps if they play or exercise in warm weather without drinking enough water.

Common causes of muscle cramps include:

  • overusing a muscle

  • dehydration

  • physical activity in warm weather

  • certain medications

  • holding a position for too long

Some children may have a particular medical condition that can lead to muscle cramps.

The following conditions may bring about muscle cramping:

  • not enough blood flow to muscles

  • compressed nerves

  • loss of certain minerals from the body 

Treatment of muscle cramps

Most muscle cramping in children is not an emergency. Simple stretching and massaging can help treat a muscle cramp. If your child gets a cramp in the calf muscle, ask him to straighten his leg and flex his foot.

You can also switch back and forth between cold compresses and warm heating pads on the affected muscle area. These treatments will usually calm the cramping after a few minutes to an hour. To prevent any dehydration, be sure to give your child lots of liquids as well.

Rest and hydrate

Heat-related illnesses are often indicated by muscle cramps, along with weakness, nausea, and vomiting. If your child has any of these symptoms, have him rest, cool off, and drink lots of liquids.


You can help your child avoid muscle cramps by offering plenty of fluids during and after playing and exercising. Urge your child to drink water or a sports drink every 15 minutes when active. Also, warn your child not to exercise too hard when it is warm or hot outside.


Encourage your child to do calf stretches before bed to prevent cramps. Ask your child to sit on the floor and stretch his legs out in front of him. Then ask your child to flex his feet, bend at the waist, and gently try to touch his toes. Your child should not point his toes.

Drinking lots of liquids

Encourage your child to drink lots of liquids throughout the day. When exercising, try to have your child drink about every 15 minutes.

When to see your doctor

  • if the muscle cramps do not disappear in a few minutes

  • if the muscle cramps are recurrent with no clear cause such as

  • intense exercise or injury

Key points

  • A muscle cramp is when a muscle in the body tenses or stiffens up.

  • The cramps are sharp, sudden, and involuntary.

  • Most muscle cramps are not an emergency. Simple stretching and massage can help.

  • To prevent muscle cramps, stretch before bed, drink lots of liquids, and avoid exercising too hard when it is hot outside.

Mark Feldman, MD, FRCPC