Osteoporosis is the most common metabolic bone disease, and various factors such as low body mass index and lack of physical activity are involved in the occurrence of this disease. The aim of this study was to evaluate the effect of circular resistance exercises, whole body vibration and their combination on 25-hydroxyvitamin D, bone mineral density and functional factors in elderly people with osteoporosis. In a randomized controlled experiment with a pre-test-post-test design, 60 elderly men with osteoporosis with an age range of 65-78 years were randomly divided into four exercise groups: Circular resistance training (CRT, n=15), whole body vibration training (WBVT, n=15), combined (CRT + WBVT, n=15), and control (n=15). CRT with an intensity of 30 to 60% of the maximum repetition strength (1RM) was performed 3 times a week for 12 weeks. WBVT were performed in the form of 10 combined lower body and upper body movements with a frequency intensity between 25 to 45 Hz, an amplitude of 5 to 8 mm, and a time of each movement of 60 to 100 seconds, While the control group maintained their usual lifestyle. Body composition variables include; Fat-free weight (LBM), soft tissue weight (SLM) and skeletal muscle weight (SMM) using Body Composition Analyzer, bone density measurement using DEXA test and 25-hydroxyvitamin D3 before and after the last training sessions. Data analysis was done by using paired sample t-test and analyze of covariance (ANCOVA) at a level less than 0.05. After 12 weeks of intervention, a significant improvement in BMD, balance, coordination, muscle strength, lean weight and skeletal muscle weight was observed after CRT and CRT + WBVT exercises in comparison with the control group. However, no significant differences were observed between the groups in the variables of weight, body mass index, lean weight, soft tissue weight, skeletal muscle weight (SMM), BMD, balance, hydroxyvitamin D3 (p> 0.05). The findings of the current research show that performing CRT, WBVT and CRT + WBV exercises as a non-pharmacological treatment method can cause a significant increase in bone density and functional indicators of elderly men and has no effect on the hormonal indicators of elderly men with osteoporosis. Further studies with long-term follow-up should be considered to confirm these findings.
