Takei Seiichiro, Hirayama Kuniaki, Okada Junichi
Int J Sports Physiol Perform. 2020 Jan 1;15(1):18-24. doi: 10.1123/ijspp.2018-0894.
The optimal load for maximal power output during hang power cleans (HPCs) from a mechanical perspective is the 1-repetition-maximum (1RM) load; however, previous research has reported otherwise. The present study thus aimed to investigate the underlying factors that determine optimal load during HPCs.
Eight competitive Olympic weight lifters performed HPCs at 40%, 60%, 70%, 80%, 90%, 95%, and 100% of their 1RM while the ground-reaction force and bar/body kinematics were simultaneously recorded. The success criterion during HPC was set above parallel squat at the receiving position.
Both peak power and relative peak power were maximized at 80% 1RM (3975.7 [439.1] W, 50.4 [6.6] W/kg, respectively). Peak force, force at peak power, and relative values tended to increase with heavier loads (P < .001), while peak system velocity and system velocity at peak power decreased significantly above 80% 1RM (P = .005 and .011, respectively). There were also significant decreases in peak bar velocity (P < .001) and bar displacement (P < .001) toward heavier loads. There was a strong positive correlation between peak bar velocity and bar displacement in 7 of 8 subjects (r > .90, P < .01). The knee joint angle at the receiving position fell below the quarter-squat position above 70% 1RM.
Submaximal loads were indeed optimal for maximal power output for HPC when the success criterion was set above the parallel-squat position. However, when the success criterion was defined as the quarter-squat position, the optimal load became the 1RM load.
从力学角度来看,抓举中产生最大功率输出的最佳负荷是1次重复最大值(1RM)负荷;然而,先前的研究报告结果并非如此。因此,本研究旨在探究决定抓举最佳负荷的潜在因素。
八名竞技奥林匹克举重运动员以其1RM的40%、60%、70%、80%、90%、95%和100%进行抓举,同时记录地面反作用力和杠铃/身体运动学数据。抓举过程中的成功标准设定为在接杠位置时深蹲超过平行位置。
最大功率和相对最大功率均在1RM的80%时达到最大值(分别为3975.7[439.1]瓦和50.4[6.6]瓦/千克)。峰值力量、最大功率时的力量及其相对值往往随着负荷增加而增加(P<.001),而最大功率时的峰值系统速度和系统速度在超过1RM的80%时显著下降(分别为P=.005和.011)。随着负荷增加,峰值杠铃速度(P<.001)和杠铃位移(P<.001)也显著下降。8名受试者中有7名的峰值杠铃速度与杠铃位移之间存在强正相关(r>.90,P<.01)。在超过1RM的70%时,接杠位置的膝关节角度低于四分之一深蹲位置。
当成功标准设定为超过平行深蹲位置时,次最大负荷确实是抓举产生最大功率输出的最佳负荷。然而,当成功标准定义为四分之一深蹲位置时,最佳负荷变为1RM负荷。