The main reason for the swelling of sedentary legs in summer is a pathological state, which is a manifestation of venous valve insufficiency in the lower limbs. During sedentary time, the blood in the lower extremities is stagnant and does not easily return to the heart, and regurgitation occurs during sedentary time due to valve insufficiency, which in turn reduces the contraction of the gastrocnemius muscle during sedentary time and weakens the muscle pump of the lower leg, all three of which simultaneously promote the occurrence of edema in the legs. Edema is more pronounced in summer, when the arterial temperature of the limb increases and dilates, resulting in greater perfusion pressure in the limb, making swelling of the sedentary leg more common in summer.