Objectives To systematically analyze the effect of high-intensity and low-intensity resistance training on glycosylated hemoglobin (HbA1c) in elderly patients with type 2 diabetes. Methods PubMed, EBSCO, Cochrane Library, Web of science, Wanfang, Chinese National Knowledge Infrastructure and Chongqing VIP were searched to collect randomized controlled trials of resistance training intervention in elderly patients with type 2 diabetes. The search time limit was from the establishment of the database to August 28, 2021, and the RevMan 5.3 and Stata 15.0 software were used for meta-analysis. Results A total of 415 patients in 8 articles were included in this study. A subgroup analysis based on control measures showed that compared with the resistance training group, the HbA1c level effect value of the non- training group was weighted mean difference (WMD) = −0.54% [95% confidence interval (CI) (−1.06%, −0.03%), P=0.04)], the HbA1c level effect value of the flexibility training group was WMD=−0.47% [95%CI (−1.05%, 0.12%), P=0.12], the HbA1c level effect value of the aerobic training group was WMD=−0.10% [95%CI (−0.71%, 0.51%), P=0.75]. Subgroup analysis of resistance strength showed that compared with the flexibility or non-resistance training group, both high-intensity [WMD=−0.99%, 95%CI (−1.16%, −0.81%), P<0.00001] and low- and medium-intensity resistance training [WMD=−0.29%, 95%CI (−0.58%, −0.01%), P=0.05] can reduce HbA1c. Compared with the high-intensity resistance training, the HbA1c level effect value of the low- and medium-intensity resistance training was WMD=0.03% [95%CI (−0.33%, 0.39%), P=0.88]. Compared with the low- and medium-intensity resistance training, the HbA1c level effect value of the low- and medium-intensity aerobic training was WMD=−0.10% [95%CI (−0.71%, 0.51%), P=0.75]. Among all the included studies, only the high-intensity resistance training group reported multiple adverse events.ConclusionsCurrent evidence suggests that elderly patients with type 2 diabetes are more suitable to choose low-to-medium-intensity resistance training to control HbA1c. It is recommended that elderly patients with type 2 diabetes take 60% to 75% of the maximum muscle strength of medium-intensity resistance training.
Although metal blocks have been widely used for reconstructing uncontained tibial bone defects, the influence of their elastic modulus on the stability of tibial prosthesis fixation remains unclear. Based on this, a finite element model incorporating constrained condylar knee (CCK) prosthesis, tibia, and metal block was established. Considering the influence of the post-restraint structure of the prosthesis, the effects of variations in the elastic modulus of the block on the von Mises stress distribution in the tibia and the block, as well as on the micromotion at the bone-prosthesis fixation interface, were investigated. Results demonstrated that collision between the insert post and femoral prosthesis during tibial internal rotation increased tibial von Mises stress, significantly influencing the prediction of block elastic modulus variation. A decrease in the elastic modulus of the metal block resulted in increased von Mises stress in the proximal tibia, significantly reduced von Mises stress in the distal tibia, decreased von Mises stress of the block, and increased micromotion at the bone-prosthesis fixation interface. When the elastic modulus of the metal block fell below that of bone cement, inadequate block support substantially increased the risk of stress shielding in the distal tibia and fixation interface loosening. Therefore, this study recommends that biomechanical investigations of CCK prostheses must consider the post-constraint effect, and the elastic modulus of metal blocks for bone reconstruction should not be lower than 3 600 MPa.