目的:血流限制(BFR)训练提供了实现肥大效应的能力,即使只施加了轻微的机械负荷。然而,其对静脉压和功能的影响尚不清楚。因此,本研究调查了与低或高机械负荷的对照运动相比,BFR训练对血管内静脉压和静脉功能的影响.方法:在随机交叉设计中,10名健康男性(27.6±6.4岁)接受了三项单侧膝关节伸肌锻炼试验,采用三种不同的训练方案,低负载-(LL-RT,个体1-重复-最大值的30%,1RM),低负荷BFR-(LL-BFR-RT,30%1RM,50%肢体闭塞压力,LOP)和高负荷阻力运动(HL-RT,75%1RM)。运动方案包含大约四组膝盖伸展运动(运动范围:0-0-95°),相隔60秒的休息。每组进行直到自愿肌肉衰竭。为了分析血管内静脉压和静脉功能的变化,每次试验前,在运动腿处放置静脉导管.虽然在整个运动试验中记录了静脉压,在每次试验之前和之后都进行了静脉动力测量研究.此外,运动期间和运动后的主观疼痛感知通过视觉模拟量表获得.单因素方差分析用于评估训练方案之间的平均差异,同时进行双向重复测量方差分析(rANOVA;时间x条件)来比较不同条件下测量随时间的变化.数据以平均值±标准偏差(SD)给出。结果:与没有静脉阻塞的运动试验相比,LL-BFR-RT的总工作量显着降低(LL-RT:1745±604kgvsLL-BFR-RT:1274±237kgvsHL-RT:1847±367kg,p=0.004),未表明运动设置(相互作用:p=0.140)或疼痛感知(相互作用:p=0.574)期间静脉压的统计差异。同样,静脉功能的静脉动力测量评估(例如静脉系统的补充时间运动后试验-LL-RT:29.7±11.0svs25.5±9.6s,LL-BFR-RT:26.6±13.0svs27.3±13.8s,HL-RT:25.9±10.9svs23.1±8.2s)未显示时间(p=0.156),条件效应(p=0.802)或它们的相互作用(p=0.382)。结论:本研究是第一个描述LL-BFR-RT对下肢静脉压和功能的急性影响的研究。与现有文献相比,LL-BFR-RT不会使运动期间的静脉压升高高于没有BFR的比较运动,并且在运动后对静脉功能没有任何不利影响。
Purpose: Blood-Flow-Restriction (BFR) training provides the ability to achieve hypertrophy effects even though only light mechanical loads are applied. However, its impact on venous pressures and function are still unknown. Therefore, the present study investigates the influence of BFR-training on intravascular venous pressure and venous function in comparison to control exercises with low or high mechanical loads. Methods: In a randomized cross-over design, ten healthy men (27.6 ± 6.4 years) underwent three trials of unilateral knee-extensor exercise with three different training protocols, low-load- (LL-RT, 30% of the individual 1-repetition-maximum, 1RM), low-load BFR- (LL-BFR-RT, 30% 1RM, 50% limb occlusion pressure, LOP) and high-load resistance exercise (HL-RT, 75% 1RM). Exercise protocols contain about four sets of knee extension exercise (Range-of-Motion: 0-0-95°), separated by 60 s of rest. Each set was performed until volitional muscle failure. For analysis of changes in intravascular venous pressures and venous function, a venous catheter was placed at the exercising leg before each trial. Whereas venous pressures were recorded throughout the exercise trials, phlebodynamometric investigations were performed before and after each trial. Furthermore, subjective pain perception during and after exercise was accessed by visual analogue scale. One-way ANOVA was used to assess mean differences between training protocols, while two-way repeated-measures ANOVA (rANOVA; time x condition) was performed to compare changes in measures over time among conditions. Data were given as means ± standard deviation (SD). Results: In comparison to the exercise trials without venous occlusion, total workload was significantly lower in the LL-BFR-RT (LL-RT: 1745 ± 604 kg vs LL-BFR-RT: 1274 ± 237 kg vs HL-RT: 1847 ± 367 kg, p = 0.004) without indicating statistical differences in venous pressures during the exercise sets (interaction: p = 0.140) or pain perception (interaction: p = 0.574). Similarly, phlebodynamometric assessment of venous function (e.g. refill-time of the venous system pre-vs. post exercise trials-LL-RT: 29.7 ± 11.0 s vs 25.5 ± 9.6 s, LL-BFR-RT: 26.6 ± 13.0 s vs 27.3 ± 13.8 s, HL-RT: 25.9 ± 10.9 s vs 23.1 ± 8.2 s) revealed no time (p = 0.156), condition effect (p = 0.802) or their interactions (p = 0.382). Conclusion: The present study is the first one describing the acute effects of LL-BFR-RT to muscle failure on venous pressures and function in comparison to a LL- and HL-RT in the lower limbs. In contrast to the existing literature, LL-BFR-RT does not elevate the venous pressures during exercise higher than a comparative exercise without BFR and does not show any adverse effects on venous function after the exercise.