Frontiers in Physiology · Oct 30, 2026
Effects of Blood Flow-Restricted Resistance Training on Cardiovascular Function and Remodeling in Rats with Early-Stage Spontaneously Hypertension
By Hong Zhang, Zhaowen Tan, Danyang Li et al.
Objective: This study aimed to investigate the effects of blood flow-restricted medium-intensity resistance training (BFRT) on cardiovascular remodeling, cardiac function, and fibrosis in early-stage spontaneously hypertensive rats (SHRs). Methods: Four-week-old male Wistar Kyoto rats and SHRs were randomly assigned to five groups: WKY, SHR sedentary control (SHR-SED), high-intensity resistance training (HIRT), medium-intensity resistance training (MIRT), and BFRT. Rats underwent 8 weeks of progressive resistance ladder training. HIRT, MIRT, and BFRT were performed at 55–75%, 35–55%, and 35–55% of 1RM, respectively, with BFRT combined with 30–40% blood flow restriction intensity. Body weight, blood pressure, heart rate, cardiac function, circulating IGF-1, SDF-1, HIF-1α, and Klotho levels were assessed. Myocardial and thoracic aortic morphology and fibrosis were evaluated using hematoxylin-eosin and Sirius red staining. Results: BFRT significantly reduced blood pressure and heart rate in SHRs, with greater reductions in diastolic blood pressure compared with conventional resistance training. BFRT improved cardiac systolic and diastolic function, reflected by increased ejection fraction, fractional shortening, and mitral E/A ratio, while attenuating left ventricular hypertrophy-related parameters. Additionally, BFRT reduced thoracic aortic wall thickness indices and decreased collagen I and total collagen deposition in the myocardium and thoracic aorta, while increasing collagen III expression and reducing the collagen I/III ratio. Compared with conventional resistance training, BFRT showed superior effects on myocardial collagen remodeling and thoracic aortic fibrosis regulation. Furthermore, BFRT increased circulating levels of IGF-1, HIF-1α, Klotho, and SDF-1. Conclusion: Blood flow-restricted medium-intensity resistance training promotes cardiovascular adaptations in early-stage SHRs by improving cardiac function, reducing myocardial and thoracic aortic fibrosis, and modulating circulating cardiovascular-related factors. These findings suggest that BFRT may represent an effective low-load resistance exercise strategy for improving cardiovascular function under hypertensive conditions.