Inclusion Criteria:  currently diagnosed with ischemic or hemorrhagic stroke by CT or MRI; right unilateral or bilateral limb with hemiparesis; age over 18 years; BMI<35 kg/m2; within 2 weeks to 12 months； the tracheotomy tube replacement; non first time standing assisted with tilt table.  Exclusion Criteria:  undergoing mechanical ventilation; postural hypotension; myocardial infarction in the first 3 months; deep vein thrombosis; angina or acute heart failure; complicated with other primary pulmonary diseases, such as tuberculosis,；pneumothorax, and chronic obstructive pulmonary disease and so on; a past episode of abdominal or chest surgery.