There are two main reasons for pain in the calf when walking: the first is due to a strain in the muscles of the calf or other soft tissues around it. For example, when walking, due to the unevenness of the road, there will be uneven force on the calf muscles, which will lead to excessive force on one muscle and strain, which will lead to the formation of swelling and inflammatory edema in the calf area, which will stimulate the peripheral nerves and cause pain in the calf area. The second situation is due to excessive walking, the calf muscles continue to be in a state of contraction and tension for a long time due to excessive fatigue and the formation of muscle tissue strain, but also the formation of chronic sterile inflammatory lesions, the resulting inflammation and lactic acid will also stimulate the peripheral nerves around the calf, there will be symptoms of pain in the calf.