Swelling of the calves when you work but not when you don’t may be caused by hypoplasia of the lower extremity venous valves, kidney disease, heart disease, hypothyroidism and other diseases. Hypoplasia of the lower extremity venous valves can lead to poor venous return in the lower legs, and the symptoms of swelling in the lower legs will appear after working for a long time or standing for a long time. In addition, patients with lower limb edema should exclude medical system diseases, such as glomerulonephritis or nephrotic syndrome in kidney disease, valvular disease in heart disease, hypothyroidism in thyroid disease, etc. These diseases can also lead to lower limb edema. These internal systemic diseases can also lead to the symptoms of lower limb swelling. Therefore, you should go to the hospital for checkups to rule out internal diseases. There are many reasons why the calves are swollen when you work, but not when you don’t, so it is recommended to go to the hospital to get a clear picture of the cause of the problem and then carry out targeted treatment.