Soreness in the left leg aggravated at night may be caused by calcium deficiency, cold at night and lumbar disc herniation. 1. Calcium deficiency: Calcium is an important element in the human body and plays an important role in the growth and development of human bones, so a lack of calcium in the body can cause leg pain. It is recommended to take some calcium tablets or eat some calcium-rich foods such as milk, soy products and so on. 2. Cold at night: the temperature is low at night, if you don’t do a good job of keeping warm when you sleep, it will lead to the leg muscles being stimulated by cold, which will make the blood vessels in the legs contract, and then ischemia will further occur, aggravating the feeling of soreness in the legs. 3. Lumbar disc herniation: This refers to the herniation of lumbar discs backward, thus compressing the nerve roots of the legs and causing pain in the lower back and lower limbs. When the left leg pain worsens at night, it is recommended to go to the hospital for examination to clarify the cause of the disease and timely treatment.