Strength measurements of the m. rectus abdominis and the vastus lateralis of the quadriceps femoris muscle are done using a Good Strength muscle test system, both static and dynamic. The measurements are undertaken preoperatively and 1 year after surgery. A CT scan of the abdomen and thigh is done both 1 month before and 1 year after surgery to provide a detailed description of the hernia dimensions, the distance between the abdominal rectus muscles, and to determine the cross sectional area of the rectus abdominis and the vastus lateralis muscle. Lung function is determined by arterial blood gas, venous oxygen saturation, forced expiratory volume (FEV1), forced- and vital capacity (FVC, VC) including B2-receptor agonist reversal test, and maximum inspiratory- and expiratory pressure (MIP/MEP) preoperatively and 1 year postoperatively. Daily arterial blood gas is measured during postoperative admission. Lung function is determined at 1-month follow-up.