Hypothermia and muscle cramps: what to know

Cold exposure changes muscle function and can cause stiffness, shivering and painful spasms. Cramps may also be worsened by exertion, dehydration or a muscle strain, so the cramp alone does not identify the cause. Hypothermia becomes more concerning when cooling affects thinking, coordination, speech or alertness. A person may stop shivering despite still being dangerously cold.

Ongoing or repeated cramps without clear cold exposure deserve a broader review. Possible contributors include dehydration, thyroid problems, reduced circulation, low vitamin D, kidney disease or loss of muscle mass.

Move to a warm, sheltered place and remove wet clothing. Dry the skin and add dry layers, blankets and a hat, warming the chest and trunk first. Use gentle warmth; avoid very hot baths, direct high heat and vigorous rubbing of numb skin. If the person is fully awake and able to swallow, offer a warm non-alcoholic drink. Rest the affected muscle and take small sips of fluid if dehydration may be contributing. Do not leave a confused or drowsy person alone.

Call emergency services for confusion, unusual drowsiness, fainting, slow or shallow breathing, severe weakness, loss of coordination or a body that feels very cold. Seek prompt assessment if cramps persist after warming, keep returning, follow an injury, or occur with pale, blue or numb skin. A clinician can check temperature, circulation, hydration and medicines rather than assuming the cramp is only from cold.

Ask whether your symptoms fit cold exposure or another cause, whether you need blood tests for thyroid, kidney or vitamin problems, and which fluids or medicines are suitable for you. Mention when the cramp began, how long it lasted, the body area affected, any wet or cold exposure, and whether weakness or numbness followed.