Nomori et al. [10] showed that MIP and MEP decrease 58% 1 week after a thoracotomy and then improve slowly to 88% 12 weeks after lung surgery compared with preoperational values. In the present study, the experimental group showed significantly improved MIP (109% vs. 91%) and MEP (100% vs. 95%) 12 weeks after surgery than the control group (Table 2). The systemic PR group also tended to prevent the decline of MIP (101% vs. 72%) compared with the control group 2 weeks after lung resection. Although the results were not significant, systemic PR tended to help recovery of respiratory muscle strength after lung resection.