Adaptations in red blood cell indices and physical performance following bungy pump training in postmenopausal women

Objective: The study examined the effects of a 12-week Bungy Pump Training (BPT) program on red blood cell (RBC) indices, physical performance, and anthropometric parameters in postmenopausal women (PW). Methods: Fifty-six PW were allocated to the BPT group (n = 30) and the Daily Activity (DA) group (n = 26). The BPT group participated in supervised 60-minute sessions three times per week for 12 weeks, while the DA group performed daily activities. RBC indices, physical performance (6-minute walk test, 6MWT), and anthropometric parameters were assessed before and after the intervention. Trial registration: Clinical Trials NCT06781541 on 17/01/2025. Results: A significant interaction was observed for mean corpuscular volume (p < 0.001), with an increase in the BPT group and a decrease in the DA group. Significant time effects were found for RBC, hemoglobin, hematocrit, and 6MWT (all p < 0.05). Following the intervention, the BPT group showed reductions in RBC and hemoglobin and an improvement in 6MWT, while the DA group also demonstrated an increase in 6MWT. A significant group effect indicated greater improvement in 6MWT (BPT: p = 0.018, d = 0.42; DA: p = 0.004, d = 0.35) in the BPT group compared with the DA group. A significant between-group difference in red cell distribution width-coefficient of variation change was observed; however, within-group changes were not significant. Additionally, reductions in waist circumference, waist-to-hip ratio, and arm circumference were observed in the BPT group. Conclusions: A 12-week BPT program was associated with changes in RBC indices and improvements in physical performance in PW. BPT was safe and well-tolerated, and may represent a feasible non-pharmacological strategy to support functional capacity and aspects of cardiovascular health in aging populations. Further studies are needed to confirm these findings.