We studied the effect of blood flow restriction (BFR) combined with low-intensity resistance training (LIRT) on lower-limb muscle strength and mass in post-middle-aged adults. The PubMed, OVID, ProQuest, Cochrane Library, EMBASE, Web of Science, and Scopus databases were used to obtain randomized controlled trials, and the effects of BFR and LIRT (BFRt) on muscle strength and mass in adults were examined. The Cochrane risk of bias tool assessed bias in the included trials. The combined effects of BFR and LIRT (BFRt) were calculated by meta-analysis, the association between muscle strength/mass and interventions was determined by meta-regression, and beneficial variables of intervention were explored by subgroup analysis. A total of 11 articles were included in the meta-analysis. The combined effects showed that BFRt significantly improved lower extremity muscle strength but not muscle mass gain. Meta-regression analysis indicated that the effect of BFRt on changes in muscle strength was correlated with frequency of the intervention. Subgroup analysis revealed that BFRt achieved greater muscle strength gains than normal activity, LIRT, and similar muscle strength gains compared to high-intensity resistance training. The increased muscle strength after BFRt was noticed with a frequency of three times a week, but not with a frequency of two times a week, and the difference between these subgroups was statistically significant. Our findings indicate that BFRt can increase lower-limb muscle strength in post-middle-aged adults. Frequency of intervention is a key variable; particularly, a schedule of three times a week is effective in improving muscle strength.

This meta-analysis examined the efficacy of low-load resistance training with blood flow restriction (LL-BFR) versus high-load resistance training (HL-RT) on muscle strength and hypertrophy, exploring factors affecting outcomes. We searched Embase, CNKI, Wanfang, PubMed, Ovid Medline, ProQuest, Cochrane Library, Embase, and Scopus from inception to July 2024. After assessing the risk of bias using the Cochrane tool, a meta-analysis was conducted to calculate the overall effect size. Subgroup analyses were performed to explore the impact of different modulating factors on training effects. LL-BFR was found to be inferior to HL-RT with regard to muscle strength gains (SMD = −0.33, 95% CI: −0.49 to −0.18, p < 0.0001). However, subgroup analyses revealed that LL-BFR achieved muscle strength gains comparable to HL-RT under individualized pressure (SMD = −0.07, p = 0.56), intermittent cuff inflation (SMD = −0.07, p = 0.65), and a higher number of training sessions (SMD = −0.12, p = 0.30). No significant difference in muscle mass gains was observed between LL-BFR and HL-RT (SMD = 0.01, p = 0.94), and this conclusion remained consistent after controlling for modulating variables. HL-RT is superior to LL-BFR in enhancing muscle strength gains. Nevertheless, under appropriate conditions, including individualized pressure prescription, intermittent cuff inflation, and a higher number of training sessions, LL-BFR can achieve muscle strength gains comparable to HL-RT, emphasizing the importance of tailored training programs. Both methods exhibit similar effects on muscle mass gains, indicating that LL-BFR serves as an effective alternative for individuals who cannot perform HL-RT because of physical limitations or injury concerns.

Background: The objective of this study was to examine the impacts of absolute cuff pressure blood flow restriction (A-BFR) training and incremental cuff pressure blood flow restriction (I-BFR) training, under equal cuff pressures, on body composition and maximal strength among untrained adults. Additionally, we aimed to compare these effects with those observed in high-load resistance training (HL-RT). Methods: Thirty-three adults without prior professional sports or resistance training experience were recruited and randomly assigned to three groups (n = 11 per group) for an 8-week training program, held three times weekly. The A-BFR group trained with a 20% 1RM load and a cuff occlusion pressure set at 190 mmHg. The I-BFR group initiated training with an occlusion pressure of 160 mmHg, which incrementally increased by 20 mmHg every two weeks, with other conditions mirroring those of the A-BFR group. The HL-RT group trained with a 70% 1RM load. Results: All three groups demonstrated a statistically significant improvement in lower-body maximal strength (p < 0.01), with no significant differences observed among the groups (p > 0.05). A notable increase in left-leg muscle mass was seen across all groups (p < 0.05). However, total muscle mass, right-leg muscle mass, fat-free mass, BMI, bone mineral density, and bone mineral content remained relatively unchanged (p > 0.05), with no significant differences among the groups (p > 0.05). Only the HL-RT group exhibited a significant increase in left-leg thigh circumference (p < 0.05), while right-leg thigh circumference remained stable (p > 0.05), with no significant intergroup differences (p > 0.05). Conclusions: While A-BFR and I-BFR did not yield statistically significant differences in overall training outcomes, A-BFR demonstrated a slightly stronger potential. A-BFR and I-BFR achieved comparable gains in muscle strength and improvements in body composition to those seen with HL-RT. However, HL-RT demonstrated more significant improvements in leg circumference.