So sleep at night is always soreness and distension consider physiological factors, may also be pathological factors, such as lower extremity venous thrombosis, diabetes, lower extremity vascular valve closure insufficiency, lumbar intervertebral disc herniation and other reasons. 1. Physiological factors, such as sitting or standing for a long time during the day, cause the blood return of the lower limbs is not good, and there is a feeling of soreness and distension, and the symptoms can be alleviated by elevating the legs at night when you sleep. 2. Lower extremity venous thrombosis: when the lower extremity veins or intermuscular formation of venous thrombosis will appear leg soreness and swelling symptoms, this situation can be clearly diagnosed by ultrasound. 3. Diabetes mellitus: Diabetes mellitus can cause vasculopathy or neuropathy in the late stage, which will lead to soreness and swelling in the lower limbs, and sometimes accompanied by numbness and ankylosis. 4. Lumbar disc herniation: Lumbar disc herniation can cause pain and numbness of the lower limbs, soreness, accompanied by lumbar pain, lumbar spine activity is limited, there can be a calf at night sleep is always sore and swollen symptoms. The calf is always sore at night need to identify the cause, to the regular hospital treatment.