Possible causes
- Muscle fatigue – after hard training or long periods of standing.
- Shortened muscles – little stretching and long sitting with bent legs.
- Dehydration and minerals – fluid loss during sport or in heat, low magnesium or potassium.
- Medication – some diuretics, statins or other drugs can make cramps worse.
- Pregnancy – cramps are common in the second half of pregnancy.
- Medical causes – diabetes, thyroid, kidney or vascular disorders.
What to check
- Magnesium and minerals – magnesium, potassium and calcium in the blood if cramps are frequent.
- Glucose and TSH – diabetes and the thyroid can affect nerves and muscles.
- Vitamin D and ferritin – deficiency is linked to muscle problems and restless legs.
- Medication list – go through it with your doctor to see whether any could be causing cramps.
What helps
- Calf stretching before bed – a few minutes of gentle stretching.
- During a cramp – pull your toes towards you, stand on the leg and gently massage the muscle.
- Enough fluids – especially after sport and in hot weather.
- A mineral-rich diet – vegetables, legumes, nuts, seeds, whole grains.
- Regular movement – and a gradual increase in training load.
When to see a doctor
See a doctor if cramps are very frequent, disrupt your sleep, or come with muscle weakness, swelling, redness or pain in one leg, numbness, or if they started after a new medication. Swelling and pain in the calf need prompt examination.