INSERM UMR1093-CAPS, Université Bourgogne Franche-Comté, UFR des Sciences du Sport, F-21000 Dijon, France.
Int J Environ Res Public Health. 2020 Oct 22;17(21):7702. doi: 10.3390/ijerph17217702.
: This study tested muscle activity (EMG) and perception of effort in eccentric (ECC) and concentric (CON) cycling before and after four sessions of both. : Twelve volunteers naïve to ECC cycling attended the laboratory six times. On day 1, they performed a CON cycling peak power output (PPO) test. They then carried-out four sessions comprising two sets of 1 to 1.5-min cycling bouts at 5 intensities (30, 45, 60, 75, and 90% PPO) in ECC and CON cycling. On day 2 and day 6 (two weeks apart), EMG root mean square of the vastus lateralis (VL), rectus femoris (RF), biceps femoris (BF), and soleus (SOL) muscles, was averaged from 15 to 30 s within each 1-min bout and perception of effort was asked after 45 s. : Before the four cycling sessions, while VL EMG was lower in ECC than CON cycling, most variables were not different. Afterwards, ECC cycling exhibited lower RF EMG at 75 and 90% PPO (all < 0.02), lower VL and BF EMG at all exercise intensities (all < 0.02), and inferior SOL EMG (all < 0.04) except at 45% PPO ( = 0.07). Perception of effort was lower in ECC cycling at all exercise intensities (all < 0.03) but 60% PPO ( = 0.11). : After four short sessions of ECC cycling, the activity of four leg muscles and perception of effort became lower in ECC than in CON cycling at most of five power outputs, while they were similar before.
本研究在进行四次 ECC 和 CON 循环后,测试了肌肉活动(EMG)和离心(ECC)和向心(CON)循环的努力感知。
12 名对 ECC 循环一无所知的志愿者六次前往实验室。在第 1 天,他们进行了 CON 循环峰值功率输出(PPO)测试。然后,他们进行了四次循环,包括两组 1 到 1.5 分钟的循环回合,在 5 个强度(30、45、60、75 和 90% PPO)的 ECC 和 CON 循环中进行。在第 2 天和第 6 天(相隔两周),从 15 到 30 秒内在每个 1 分钟回合内平均取 15 秒的股外侧肌(VL)、股直肌(RF)、股二头肌(BF)和比目鱼肌(SOL)的 EMG 均方根,并且在 45 秒后询问努力感知。
在进行四次循环之前,虽然 ECC 中的 VL EMG 低于 CON 循环,但大多数变量没有差异。之后,ECC 循环在 75%和 90%PPO 时显示出较低的 RF EMG(均 < 0.02),在所有运动强度下显示出较低的 VL 和 BF EMG(均 < 0.02),以及较低的 SOL EMG(除 45%PPO 外,均 < 0.04)( = 0.07)。ECC 循环在所有运动强度下的努力感知均较低(均 < 0.03),但在 60%PPO 时除外( = 0.11)。
在四次短暂的 ECC 循环后,与 CON 循环相比,在大多数五个功率输出中,四条腿部肌肉的活动和努力感知在 ECC 中变得更低,而在之前它们是相似的。