Soreness and swelling of the calf may be caused by physiological factors such as standing for a long time and getting cold, or it may be caused by pathological factors such as myofasciitis of the calf, nerve compression, vascular lesions of the lower limbs, trauma, etc., which require timely consultation to find out the causes. 1. Physiological factors: after standing for a long time or getting cold, the muscles of the calf will be stimulated by undesirable factors, which will cause soreness and discomfort, and most of them can be relieved after recuperation. 2. Calf myofasciitis: due to repeated pulling of the calf muscle or fascia, local congestion, oozing and other aseptic inflammation will occur, resulting in soreness and swelling of the calf. 3. Nerve compression: the more common ones are lumbar intervertebral disc herniation, pyriform muscle syndrome, etc. Due to nerve compression, it will lead to recurrent soreness and swelling of the calf, and some of them will have numbness and weakness of the calf. 4. Lower limb vascular disease: when there are lower limb varicose veins or deep vein thrombosis and other diseases, due to the blood circulation is not smooth, thus causing the calf soreness and swelling, often accompanied by a drop in the calf skin temperature, hyperpigmentation, swelling and so on. 5. Trauma: When running, jumping and other strenuous exercise, the muscles of the calf are pulled, which will release too much lactic acid, and some serious cases may lead to muscle damage, which will result in soreness and swelling of the calf. Calf always appear soreness, exclude physiological factors, we should promptly consult the appropriate examination, please doctor to clarify the cause of the disease, and targeted treatment.