Background/Aims: The aim was to investigate the effectiveness of exercise on muscle strength, lung capacity, spinal mobility, endurance, and quality of life (QoL) in postmenopausal osteoporosis patients without vertebral fractures. Materials and Methods: This study was conducted with 41 postmenopausal osteoporosis patients (aged 45-65 years) without osteoporotic fractures. Patients were randomized into 2 groups. The patients in the exercise group (EG) were given an exercise regimen (breathing, stretching, relaxation, balance, and strengthening exercises) 3 times a week for 8 weeks at the department. Patients in the control group were kept on their current medical treatment. A Cybex Isokinetic Dynamometer and a Saunders digital inclinometer were used to assess back extensor muscle strength and spinal mobility. Pulmonary function tests were performed with a Jaeger spirometer. "Timed loaded standing" method, Quality of Life Questionnaire of the European Foundation for Osteoporosis 41 (QUALEFFO-41) and Short Form Health Survey 36 (SF-36) were used to evaluate the impact of exercise on back endurance and QoL respectively. Results: Baseline demographic and clinical characteristics were similar between the 2 groups. At the end of the study, statistically significant improvements were noted in the EG's back extensor strength and endurance compared to baseline values (P < .05). Vital capacity, forced vital capacity, forced expiratory volume during the first second, maximal mid-expiratory flow rate, maximum inspiratory pressure measurements, and scores for QoL (physical function, mental function sub-scores, and total QUALEFFO-41 score, physical function, and vitality sub-scores of SF-36) were also significantly improved in the EG (P < .05). Spinal mobility of patients remained unchanged at the end of the study for both groups (P > .05). Conclusion: Muscle strength, trunk endurance, pulmonary functions, and QoL are known to be affected in postmenopausal osteoporosis patients. The findings supported that significant improvements can be achieved in these parameters even with appropriate short-term exercise in fracturefree periods.