PDF(Pubmed)
Abstract：
This study assessed muscle activity (root mean square, RMS, and median frequency, MDF) to evaluate the acute response to blood flow restriction (BFR) resistance exercise (RE) and conventional moderate intensity (MI) RE. We also performed exploratory analyses of differences based on sex and exercise-induced hypoalgesia (EIH). Fourteen asymptomatic individuals performed four sets of unilateral leg press with their dominant leg to volitional fatigue under two exercise conditions: BFR RE and MI RE. Dominant side rectus femoris (RF) and vastus lateralis (VL) muscle activity were measured using surface electromyography (sEMG) through exercise. RMS and MDF were calculated and compared between conditions and timepoints using a linear mixed model. Pressure pain thresholds (PPT) were tested before and immediately after exercise and used to quantify EIH. Participants were then divided into EIH responders and nonresponders, and the differences on RMS and MDF were compared between the two groups using Hedges\' g. RMS significantly increased over time (RF: p = 0.0039; VL: p = 0.001) but not between conditions (RF: p = 0.4; VL: p = 0.67). MDF decreased over time (RF: p = 0.042; VL: p < 0.001) but not between conditions (RF: p = 0.74; VL: p = 0.77). Consistently lower muscle activation was found in females compared with males (BRF, RF: g = 0.63; VL, g = 0.5. MI, RF: g = 0.72; VL: g = 1.56), with more heterogeneous findings in MDF changes. For BFR, EIH responders showed greater RMS changes (Δ RMS) (RF: g = 0.90; VL: g = 1.21) but similar MDF changes (Δ MDF) (RF: g = 0.45; VL: g = 0.28) compared to nonresponders. For MI, EIH responders demonstrated greater increase on Δ RMS (g = 0.61) and decrease on Δ MDF (g = 0.68) in RF but similar changes in VL (Δ RMS: g = 0.40; Δ MDF: g = 0.39). These results indicate that when exercising to fatigue, no statistically significant difference was observed between BFR RE and conventional MI RE in Δ RMS and Δ MDF. Lower muscle activity was noticed in females. While exercising to volitional fatigue, muscle activity may contribute to EIH.
摘要：
这项研究评估了肌肉活动(均方根，RMS,和中值频率，MDF）评估对血流限制（BFR）抗阻运动（RE）和常规中等强度（MI）RE的急性反应。我们还基于性别和运动引起的痛觉减退（EIH）对差异进行了探索性分析。在两种运动条件下：BFRRE和MIRE，十四名无症状者用优势腿进行了四组单侧腿部按压以进行自愿疲劳。通过运动使用表面肌电图（sEMG）测量显性侧股直肌（RF）和股外侧肌（VL）肌肉活动。使用线性混合模型计算RMS和MDF并在条件和时间点之间进行比较。在运动前和运动后立即测试压力疼痛阈值（PPT），并用于量化EIH。然后将参与者分为EIH响应者和无响应者，使用Hedges\'g比较两组之间RMS和MDF的差异。RMS随时间显着增加（RF：p=0.0039；VL：p=0.001），但在条件之间没有增加（RF：p=0.4；VL：p=0.67）。MDF随时间降低(RF:p=0.042;VL:p<0.001),但条件之间没有降低(RF:p=0.74;VL:p=0.77)。与男性相比，女性的肌肉激活持续较低(BRF，RF:g=0.63;VL,g=0.5。MI,RF：g=0.72；VL：g=1.56），MDF变化的异质性发现更多。对于BFR，与无反应者相比，EIH反应者显示出更大的RMS变化（ΔRMS）（RF：g=0.90；VL：g=1.21），但MDF变化相似（ΔMDF）（RF：g=0.45；VL：g=0.28）。对于MI,EIH反应者在RF中表现出ΔRMS（g=0.61）的增加和ΔMDF（g=0.68）的减少，但VL的变化相似（ΔRMS：g=0.40；ΔMDF：g=0.39）。这些结果表明，当锻炼到疲劳时，在ΔRMS和ΔMDF中，BFRRE和常规MIRE之间未观察到统计学上的显着差异。女性的肌肉活动较低。在锻炼意志疲劳时，肌肉活动可能有助于EIH。
