A tight and protruding piece of calf without pain, consider fat hernia or muscle hernia, muscle strain, osteochondroma and so on. 1. fat hernia or muscle hernia: because of the fascial defect, calf fat or muscle tissue protrudes through the defect, usually no obvious pain, no special treatment. 2. Muscle strain: due to walking too much or strenuous exercise caused by calf muscle strain, muscle swelling, localized protrusion. You can relax the muscle with local massage. 3. Osteochondroma: belongs to a kind of benign tumor, slow growth, local lump, if the growth rate is fast, oppression of the surrounding tissues caused by pain. Calf tight protruding a piece of pain can go to the hospital to check, clear cause and whether the need to deal with.