Explore the vast range of titles available.

ObjectiveTo examine the effects of autoregulated (AUTO) and non-autoregulated (NAUTO) blood flow restriction (BFR) application on adverse effects, performance, cardiovascular and perceptual responses during resistance exercise.MethodsFifty-six healthy participants underwent AUTO and NAUTO BFR resistance exercise in a randomised crossover design using a training session with fixed amount of repetitions and a training session until volitional failure. Cardiovascular parameters, rate of perceived effort (RPE), rate of perceived discomfort (RPD) and number of repetitions were investigated after training, while the presence of delayed onset muscle soreness (DOMS) was verified 24 hours post-session. Adverse events during or following training were also monitored.ResultsAUTO outperformed NAUTO in the failure protocol (p<0.001), while AUTO scored significantly lower for DOMS 24 hours after exercise (p<0.001). Perceptions of effort and discomfort were significantly higher in NAUTO compared with AUTO in both fixed (RPE: p=0.014, RPD: p<0.001) and failure protocol (RPE: p=0.028, RPD: p<0.001). Sixteen adverse events (7.14%) were recorded, with a sevenfold incidence in the fixed protocol for NAUTO compared with AUTO (NAUTO: n=7 vs AUTO: n=1) and five (NAUTO) vs three (AUTO) adverse events in the failure protocol. No significant differences in cardiovascular parameters were found comparing both pressure applications.ConclusionAutoregulation appears to enhance safety and performance in both fixed and failure BFR-training protocols. AUTO BFR training did not seem to affect cardiovascular stress differently, but was associated with lower DOMS, perceived effort and discomfort compared with NAUTO.Trial registration number NCT04996680.

Low-load blood flow restriction training (BFRT) has been shown to induce a significant increase in muscle activation. However, low-load BFRT to augment the post-activation performance enhancement (PAPE) has not been previously examined. This study aimed to examine the PAPE of low-intensity semi-squat exercises with varying pressure BFRT on vertical height jump performance. Twelve elite athletes from the Shaanxi Province women’s football team volunteered to participate in this study for 4 weeks. Participants completed four testing sessions that included one of the following at random: (1) non-BFRT, (2) 50% arterial occlusion pressure (AOP), (3) 60% AOP, or (4) 70% AOP. Muscle activity of the lower thigh muscles was recorded using electromyography (EMG). Jump height, peak power output (PPO), vertical ground reaction forces (vGRF), and rate of force development (RFD) were recorded for four trials. Two-factor repeated measures analysis of variance (ANOVA) showed that semi-squat with varying pressure BFRT had a significant impact on the measured muscle EMG amplitude and MF value of vastus medialis, vastus lateralis, rectus femoris, and biceps femoris (P < 0.05), and MF value decreased with increasing pressure. Muscle activation (EMG amplitude) did not change further. The EMG amplitude of the gluteus maximus was significantly decreased by semi-squat training with different pressures (P < 0.05), while that of the gluteus maximus muscle was gradually increased by non-BFR with semi-squat training (P > 0.05). The 50% and 60% AOP BFRTs significantly increased jump height, peak power, and force increase rate (RFD) after 5 min and 10 min of rest (P < 0.05). This study further confirmed that low-intensity BFRT can significantly increase lower limb muscle activation, induce PAPE, and improve vertical height jump in female footballers. In addition, 50% AOP continuous BFRT is recommended for warm-up activities.

Background It is recommended to prescribe sets to volitional muscular failure (e.g., 4 sets) or a fixed repetition scheme of 75 repetitions (1 × 30, 3 × 15) in low-load resistance exercise with blood flow restriction (BFR-RE). While prior studies suggest both protocols may elicit similar muscular adaptations, the extent to which this is explained by matched exercise volume remains unclear. Objectives This systematic review and meta-analysis evaluated the number of repetitions performed during four sets of low-load BFR-RE to volitional muscular failure and compared these with the fixed 75-repetition scheme. The goal was to determine whether the two protocols yield similar total and per-set repetition volumes. Methods On 10/31/2024, two databases (PubMed ® and Scopus) were used to identify studies that applied a protocol of four sets to volitional muscular failure in BFR-RE with a load of ≤ 50% of one repetition maximum (1RM), regardless of the outcome investigated. Mean repetition data were pooled using a random-effects meta-analysis. One-sample t-tests compared per-set and total volumes to the reference scheme (1 × 30, 3 × 15). Results Across 25 studies (47 means; n  = 678), the estimated total repetitions performed to failure was 73.1 (95% CI: 61.1 to 85.2). Per-set means were 36.0 (95% CI: 30.5 to 41.4), 14.7 (95% CI: 12.2 to 17.1), 11.5 (95% CI: 9.2 to 13.8), and 10.4 repetitions (95% CI: 8.1 to 12.7) for sets 1 through 4, respectively. Conclusion Four sets of BFR-RE to volitional muscular failure produce similar total repetition volume compared to the commonly implemented fixed 75-repetition scheme, though the distribution of repetitions per set differs. These findings provide insight into the mechanical equivalence of two widely used BFR-RE prescriptions. Key Points This study demonstrates that performing four sets of low-load BFR-RE to volitional muscular failure yields similar total repetition volumes as the commonly studied and traditionally recommended fixed 75-repetition protocol (1 × 30, 3 × 15), despite meaningful differences in per-set repetition counts. Lower external loads and higher occlusion pressures were associated with slightly greater total repetitions—likely reflecting study design choices rather than physiological effects. Personalized pressure strategies affected repetitions achieved, with notable performance declines across later sets. These findings highlight the flexibility of BFR-RE prescription while underscoring the importance of fatigue management and set progression. The fixed 75-rep protocol may offer a more tolerable and practical option for many populations, particularly in rehabilitation or clinical settings where adherence is a key concern.

The present study was conducted to evaluate the effect of blood flow restriction (BFR) training on cardiac resistance to isoproterenol (ISO) induced heart injury in old rats and examined the hypothesis that BFR training may interfere with age-associated impairment of mitochondria by the inhibitory phosphorylation of GSK-3β at Ser9. Old male Wistar rats were divided into the following six groups: CTL (control), ISO (isoproterenol-treated), Sh + ISO (sham-operated plus ISO), BFR + ISO (blood flow restriction plus ISO), Sh-Ex + ISO (sham-operated subjected to exercise and ISO), and BFR-Ex + ISO (blood flow restriction along with exercise and ISO). 10 weeks of exercise training was considered. Then, cardiac injury was induced and physiological, histological, and biochemical parameters were recorded and assessed. Compared to CTL group, isoproterenol administration significantly reduced the systolic arterial pressure (SAP), left-ventricular systolic pressure (LVSP), and ± dp/dt max (P < 0.05). BFR training improved these parameters in the way that BFR-Ex + ISO group had higher SAP, LVSP and ± dp/dt max (P < 0.05) and lower LVEDP (left-ventricular end diastolic pressure) (P < 0.01) than untrained and Sh-Ex + ISO groups. The pS9-GSK-3β and pS9-GSK-3β/GSK-3β ratio were increased in the BFR-Ex + ISO group compared to CTL, ISO, Sh + ISO, and BFR + ISO groups (P < 0.05). The level of plasma cardiac Troponin-I and the severity of the injuries were significantly reduced in BFR-Ex + ISO group versus other cardiac damaged groups. In conclusion, our findings clearly confirmed the cardio-protective effect of BFR training against ISO-induced myocardial injury. Increased phosphorylated GSK-3β and angiogenesis in this model of exercise justify the resistance of old hearts facing stressful situations.