What causes calf pain?

A sudden push-off, sprint, jump, or overstretch can injure the calf and cause a muscle strain with tenderness and pain during contraction. A direct knock may produce a muscle contusion, with bruising or swelling. Achilles tendinitis usually causes pain lower down near the heel, often linked to repeated loading. Compartment syndrome involves rising pressure within a confined muscle space and can cause intense, tight pain with swelling or altered sensation. Calf pain can also come from a clot or another circulation problem, which may cause one-sided swelling, warmth, redness, or tenderness. These patterns overlap, so a new unexplained calf problem should be assessed rather than massaged.

After a clear minor injury, protect the leg from provoking activity, use comfortable gentle movement, and gradually reload it as pain settles. Elevation may help swelling. Do not apply deep massage or strenuous stretching to a swollen, warm, unexplained calf before medical advice. A clinician can examine the tissues and circulation. Sports massage may be appropriate for selected muscular problems after serious causes have been excluded.

Seek urgent medical care for sudden one-sided calf swelling, warmth, redness, unexplained tenderness, or calf pain with chest pain or breathlessness. Also seek urgent help for severe pain out of proportion to an injury, a very tense calf, new numbness, or difficulty moving the foot. Arrange review for persistent pain, bruising, weakness, or difficulty walking.

Does this look like a strain, contusion, tendon problem, or something affecting circulation? Do I need an ultrasound or another test? When can I resume sport? Is massage safe for my symptoms?