Abstract: Objective  To investigate the effect of resistance exercise on bone mineral density (BMD) in maintenance hemodialysis (MHD) patients by implementing lower limb resistance exercise rehabilitation training. Methods  MHD patients on regular dialysis at Shanghai Jing 'an District Zhabei Central Hospital from October 2022 to November 2023 were selected as the study subjects. Patients were randomly divided into either an exercise rehabilitation group or a control group. The control group received routine treatment, while the exercise rehabilitation group received additional intra-dialytic lower limb resistance exercise training based on routine treatment. The follow-up period was 6 months. Changes in BMD, skeletal muscle index (SMI), calcium, phosphorus, parathyroid hormone, osteocalcin (OC), N-terminal propeptide of type I procollagen (PINP), and beta C-terminal telopeptide of type I collagen (β-CTX) were compared between the two groups.  Results  A total of 90 patients were enrolled, with 45 patients in each group. Before the study, there were no statistically significant differences in SMI and BMD between the two groups (t=0.759, P=0.450; t=0.003, P=0.997). After 6 months of treatment, both SMI [(7.73 ± 1.01) kg/m²] and BMD [(0.470 ± 0.089) g/cm²] in the exercise rehabilitation group increased compared to pre-study levels [SMI(7.03±1.20)kg/m2, BMD (0.419±0.098)g/cm2], and the comparative differences were statistically significant (t=-2.615, P=0.002; t=-0.867, P=0.012). Compared to the control group during the same period (SMI 7.19±1.13 kg/m2, BMD 0.418±0.098 g/cm2)，the differences were also statistically significant (t=-2.390, P=0.019, t=-2.598, P=0.011). Before the study, there were no statistically significant differences in OC, β-CTX, and PINP between the two groups (Z=-0.105, P=0.292; Z=-1.126, P=0.260; Z=-0.195, P=0.846). After 6 months of treatment, the differences in OC, β-CTX, and PINP between the exercise rehabilitation group and the control group were statistically significant (Z=-3.531, P＜0.001; Z=-2.841, P=0.005; Z=-3.635, P＜0.001).  Conclusion   A 6-month lower limb resistance exercise rehabilitation program for MHD patients is safe and effective, improving muscle mass, increasing bone mineral density, and reducing the risk of osteoporosis.

Key words: Resistance exercise, Hemodialysis, Bone density