Objective To explore the effects of pulmonary rehabilitation training on respiratory function,muscle strength,muscle mass,exercise endurance in patients with chronic obstructive pulmonary disease(COPD)and sarcopenia.Methods A total of 100 patients with COPD and sarcopenia admitted to Taixing People's Hospital from June 2022 to June 2023 were selected as the research subjects.These patients were randomly divided into control group and observation group by the envelope method,with 50 patients in each group.The patients in the control group were given conventional COPD treatment,and the patients in the observation group were given conventional COPD treatment combined with pulmonary rehabilitation training,and all patients were treated for 6 months.The pulmonary function[forced vital capacity(FVC),forced expiratory volume in the one second(FEV1),and FEV1/FVC ratio]of patients in the two groups was evaluated by spirometer at admission,4 weeks,12 weeks,and 6 months of training.The COPD assessment test(CAT)questionnaire and the modified Medical Research Council dyspnea scale(mMRC)score were used to evaluate the degree of dyspnea of patients in the two groups.The skeletal muscle index(SMI)of patients in the two groups was measured by bioelectrical impedance analyzer,the handgrip strength(HGS)of patients in the two groups was measured by electronic handgrip dynamometer,and the exercise tolerance of patients in the two groups was evaluated by 6-minute walk test.Patients who needed to be re-hospitalized during the study period filled in the re-hospitalization registration form,and the re-hospitalization rate was calculated.Results There was no statistically significant difference in FVC,FEV,,and FEV1/FVC ratio of patients between the two groups at admission(P＞0.05);the FVC,FEV1,and FEV1/FVC ratio of patients at 4 weeks,12 weeks,and 6 months of training were significantly high-er than those at admission in the control group and the observation group(P＜0.05);after 4 weeks,12 weeks,and 6 months of training,the FVC,FEV1,and FEV1/FVC ratio of patients in the observation group were significantly higher than those in the control group(P＜0.05).There was no statistically significant difference in CAT and mMRC scores of patients between the two groups at admission(P＞0.05);the CAT and mMRC scores of patients at 4 weeks,12 weeks,and 6 months of training were significantly lower than those at admission in the control group and the observation group(P＜0.05);after 4 weeks,12 weeks,and 6 months of training,the CAT and mMRC scores of patients in the observation group were significantly lower than those in the control group(P＜0.05).There was no significant difference in SMI and HGS levels of patients between the two groups at admission(P＞0.05);the SMI and HGS levels of patients at 4 weeks,12 weeks and 6 months of training were significantly higher than those at admission in the control group and the observation group(P＜0.05);after 4 weeks,12 weeks and 6 months of training,the SMI and HGS levels of patients in the observation group were significantly higher than those in the control group(P＜0.05).There was no significant difference in the 6-minute walking distance between the two groups at admission(P＞0.05);the 6-minute walking distances of patients at 4 weeks,12 weeks and 6 months of training were significantly higher than those at admission in the control group and the observation group(P＜0.05);after 4 weeks,12 weeks and 6 months of training,the 6-minute walking distance of patients in the observation group was significantly higher than that in the control group(P＜0.05).The re-hospitalization rate of patients in the observation group and the control group was 14％(7/50)and 32％(16/50),respectively;the re-hospitalization rate of patients in the observation group was significantly lower than that in the control group(x2=4.574,P＜0.05).Conclusion Pulmonary rehabilitation training can effectively improve the respiratory function of patients with COPD and sarcopenia,reduce their degree of dyspnea,enhance muscle strength,muscle mass and exercise tolerance,and reduce the re-hospitalization rate.