The most common reasons for two calves especially heavy fatigue are over-exercise, lumbar disc herniation, varicose veins of the lower limbs, fasciitis and so on. 1. Excessive exercise: if the patient is engaged in strenuous sports, it is easy to cause lactic acid accumulation in the patient’s calves, lactic acid metabolism process is easy to induce two calves heavy. 2. Herniated lumbar intervertebral discs: when the herniated lumbar intervertebral discs compress the peripheral nerve roots, it is easy to cause pain and numbness in the lower limbs, and it can also show heavy fatigue in the calves. 3. Varicose veins of the lower limbs: if the patient’s venous valves are dysfunctional, it is easy to cause the flexion and expansion of the veins of the lower limbs, which will show the discomfort of the patient’s calves, and even swelling and abnormal sensation. 4. Fasciitis: If the patient has fasciitis at the calf, it is easy to attack when stimulated by external cold, and then the two calves are particularly heavy and tired. Caused by two calves especially heavy fatigue causes more, but also may be related to lower extremity venous thrombosis, lumbar spinal stenosis and other reasons, if the symptoms continue to have no relief, it is recommended to go to the hospital in a timely manner to find out the cause of the disease, by the doctor targeted treatment.