Background: Osteoporosis in postmenopausal women and individuals with rheumatoid arthritis (RA) is marked by accelerated bone mineral density (BMD) loss and heightened fracture risk. Despite widespread pharmacological treatment, concerns about long term efficacy, safety, and adherence persist. This systematic review evaluates the effectiveness of lifestyle and physical activity interventions in improving bone health markers, in these high risk groups.

Methods: We conducted a systematic review in accordance with PRISMA guidelines. A comprehensive search of PubMed, Scopus, Web of Science, and Google Scholar identified English language randomized controlled trials and quasi experimental studies published between 2015 and 2025. Eligible studies evaluated lifestyle and physical activity interventions targeting BMD, bone metabolism markers, pain, or physical function in postmenopausal women or patients with RA. Data were narratively synthesized, and methodological quality was assessed using the Cochrane Risk of Bias tool.

Results: The evidence indicates that isolated calcium and vitamin D supplementation, even at varying dosages, yielded negligible effects on BMD restoration and fracture risk reduction. In contrast, structured exercise programs—including aerobic and resistance training—consistently improved BMD, muscle mass, physical function, and, particularly in RA patients, reduced pain and disease activity. Multimodal interventions integrating resistance training, nutritional counseling, and behavioral change strategies demonstrated superior efficacy in enhancing BMD, musculoskeletal function, and laboratory markers of bone metabolism. Educational interventions grounded in behavioral models improved motivation, self efficacy, and adherence, resulting in measurable gains in densitometric indices and disease activity.

Conclusion: Multimodal lifestyle interventions provide greater benefits than single component approaches for bone health management in high risk populations and should be prioritized as personalized, multifactorial adjuncts to standard care for postmenopausal osteoporosis and RA.