Department of Health, Exercise Science, and Recreation Management, Kevser Ermin Applied Physiology Laboratory, The University of Mississippi, University, MS, USA.
USF Muscle Lab, Exercise Science Program, University of South Florida, Tampa, FL, USA.
Eur J Sport Sci. 2020 Jun;20(5):650-659. doi: 10.1080/17461391.2019.1664640. Epub 2019 Sep 23.
Low-load exercise performed to or near task failure appears to result in similar skeletal muscle adaptations as low-load exercise with the addition of blood flow restriction (BFR). However, there may be a point where the training load becomes too low to stimulate an anabolic response without BFR. This study examined skeletal muscle adaptions to very low-load resistance exercise with and without BFR. Changes in muscle thickness (MTH), strength, and endurance were examined following 8-weeks of training with a traditional high-load [70% 1RM,(7000)], low-load [15% 1RM,(1500)], low-load with moderate BFR [15%1RM + 40%BFR(1540)], or low-load with greater BFR [15% 1RM + 80%BFR(1580)]. 1RM strength changes were greater in the 7000 condition [2.09 (95% CI = 1.35-2.83) kg] compared to all low-load conditions. For isometric and isokinetic strength, there were no changes. For endurance, there was a main effect for time [mean pre to post change = 7.9 (4.3-11.6) repetitions]. At the 50% site, the mean change in MTH in the 7000 condition [0.16 (0.10-0.22) cm] was greater than all low-load conditions. For the 60% site, the mean change in MTH [0.15 (0.08-0.22)] was greater than all low-load conditions. For the 70% site there was a main effect for time [mean pre to post change = 0.09 (0.05-0.14 cm]. All groups increased muscle size; however, this response was less in all very low training conditions compared to high-load training. 1RM strength increased in the 7000 condition only, with no other changes in strength observed.
低负荷运动，无论是在接近任务失败的情况下进行，还是在加上血流限制（BFR）的情况下进行，似乎都会导致类似的骨骼肌适应。然而，可能存在一个点，即训练负荷变得太低，以至于没有 BFR 就无法刺激合成代谢反应。本研究检查了非常低负荷阻力运动结合和不结合 BFR 的骨骼肌适应。在经过 8 周的训练后，检查了肌肉厚度（MTH）、力量和耐力的变化，训练方案包括传统的高负荷[70% 1RM（7000）]、低负荷[15% 1RM（1500）]、低负荷结合中度 BFR [15%1RM+40%BFR（1540）]或低负荷结合更大 BFR [15% 1RM+80%BFR（1580）]。1RM 力量变化在 7000 条件下更大[2.09（95%置信区间= 1.35-2.83）kg]，与所有低负荷条件相比。对于等长和等速力量，没有变化。对于耐力，时间有主要影响[平均前后变化=7.9（4.3-11.6）次]。在 50%的部位，7000 条件下 MTH 的平均变化[0.16（0.10-0.22）cm]大于所有低负荷条件。对于 60%的部位，MTH 的平均变化[0.15（0.08-0.22）]大于所有低负荷条件。对于 70%的部位，时间有主要影响[平均前后变化=0.09（0.05-0.14）cm]。所有组的肌肉大小都增加了；然而，与高负荷训练相比，所有非常低的训练条件下的这种反应都较小。只有在 7000 条件下，1RM 力量增加，其他力量没有变化。
