School of Sports Health, Guangdong Vocational Institute of Sport, Guangzhou, Guangdong, China.
School of Athletic Performance, Shanghai University of Sport, Shanghai, China.
PeerJ. 2023 Aug 15;11:e15863. doi: 10.7717/peerj.15863. eCollection 2023.
This study investigated the grouped and individualized load-velocity profile (GLVP ILVP) in Bulgarian split squat using Smith machine and free weight. Seventy five recreational male lifters completed two incremental loading tests of Bulgarian split squat. Mean velocity was measured by a linear-position transducer (GymAware). Linear regression equation was applied to construct the GLVP and ILVP. The agreement of predicted %1RM and measured %1RM was assessed by a combination of intraclass correlation coefficient (ICC), coefficient of variation (CV), standard error of measurement (SEM) and Bland-Altman analysis. Acceptable validity was defined as ICC > 0.75, CV ≤ 10% and ≥ 0.05 (a paired Wilcoxon signed-rank test). A very high level of inverse load-velocity relationships were demonstrated in Bulgarian split squat ( = - 0.92) with free weights and a Smith machine. ILVP (ICC ≥ 0.98, CV ≤ 8.73%, ≥ 0.56) was valid enough to predict the %1RM, but GLVP of both limbs revealed large CVs in free weights (CV: 15.4%,15.63%) and a Smith machine (CV: 11.24%, 12.25%). Cross-validation between the actual %1RM and predicted %1RM using free weights and a Smith machine ILVP was not acceptable ( ≤ 0.03, CV ≥ 14.07%). A very high level of inverse relationship were observed between %1RM and MV in Bulgarian split squat using free weights and a Smith machine, indicating individualized load velocity properties, and the ILVP showed high between-devices variability in both scenarios. Using velocity as a measure of loading intensity in Bulgarian split squat needs to consider the individualized load velocity properties, and difference between free weights and a Smith machine.
本研究采用史密斯机和自由重量两种方式对保加利亚分腿蹲的分组和个体化负荷-速度曲线（GLVP 和 ILVP）进行了研究。75 名男性业余举重运动员完成了两次保加利亚分腿蹲的递增负荷测试。线性位置传感器（GymAware）测量平均速度。线性回归方程用于构建 GLVP 和 ILVP。通过组合组内相关系数（ICC）、变异系数（CV）、测量标准误差（SEM）和 Bland-Altman 分析来评估预测 1RM%和实测 1RM%的一致性。可接受的有效性定义为 ICC>0.75、CV≤10%和≥0.05（配对 Wilcoxon 符号秩检验）。使用自由重量和史密斯机进行保加利亚分腿蹲时，显示出非常高的反向负荷-速度关系（= -0.92）。ILVP（ICC≥0.98，CV≤8.73%，≥0.56）足以预测 1RM%，但两条腿的 GLVP 在自由重量（CV：15.4%、15.63%）和史密斯机（CV：11.24%、12.25%）中显示出较大的 CV。使用自由重量和史密斯机进行交叉验证时，实际 1RM%和预测 1RM%之间的 ILVP 不可接受（≤0.03，CV≥14.07%）。在使用自由重量和史密斯机进行保加利亚分腿蹲时，1RM%和 MV 之间观察到非常高的负相关，表明存在个体负荷速度特性，在两种情况下，ILVP 都显示出设备间较大的变异性。在保加利亚分腿蹲中，使用速度作为负荷强度的衡量标准时，需要考虑个体负荷速度特性以及自由重量和史密斯机之间的差异。
