Abstract：
Our previous study showed that daily six maximal eccentric contractions that were performed 5 days a week for 4 weeks increased maximal voluntary isometric (MVC-ISO), concentric (MVC-CON), and eccentric contraction (MVC-ECC) strength of the elbow flexors and muscle thickness of biceps brachii and brachialis (MT) by 8.3 ± 4.9%, 11.1 ± 7.4%, 13.5 ± 11.5%, and 10.6 ± 5.1%, respectively. In the present study, we tested the hypothesis that the muscle strength and MT would still increase when the training intensity was reduced to 2/3 or 1/3 of the peak MVC-ECC torque. Thirty-six healthy young (19-24 years) adults who had not performed resistance training were placed to three groups (n = 12/group): 2/3MVC or 1/3MVC that performed six eccentric contractions with 2/3 or 1/3 MVC-ECC load using a dumbbell 5 days a week for 4 weeks or control group that did not perform any training. Changes in the MVC-ISO, MVC-CON, MVC-ECC torque, and MT before and after the 4-week period were compared among the groups and with the group of the previous study in which six maximal eccentric contractions were performed 5 days a week for 4 weeks (MVC group; n = 12). The control and 1/3MVC groups showed no significant changes in any measures. Significant (p < 0.05) increases in MVC-ISO (10.3 ± 11.4%), MVC-CON (10.9 ± 9.5%), and MVC-ECC (9.3 ± 8.8%) torque and MT (10.1 ± 9.2%) were observed for the 2/3MVC group. These changes were not significantly different from those of the MVC group. These results suggest that the 2/3-intensity eccentric contractions with a dumbbell are as effective as maximal-intensity isokinetic eccentric contractions to induce muscle adaptations.
摘要：
我们先前的研究表明，每周5天进行4周的每日六次最大偏心收缩增加了最大自愿等距（MVC-ISO），同心（MVC-CON），肘屈的偏心收缩（MVC-ECC）强度和肱二头肌和肱二头肌（MT）的肌肉厚度为8.3±4.9％，11.1±7.4%，13.5±11.5%,10.6±5.1%，分别。在本研究中,我们检验了以下假设:当训练强度降低到MVC-ECC扭矩峰值的2/3或1/3时,肌肉力量和MT仍将增加.未进行阻力训练的36名健康年轻（19-24岁）成年人被分为三组（n=12/组）：2/3MVC或1/3MVC进行6次偏心收缩，其中2/3或1/3MVC-ECC负荷使用哑铃每周5天，共4周，对照组则未进行任何训练。MVC-ISO的变化，MVC-CON,MVC-ECC扭矩，在各组之间以及与先前研究的每周5天进行6次最大偏心收缩，共4周（MVC组；n=12）的组中，比较了4周前后的MT和MT。对照组和1/3MVC组在任何措施上都没有显着变化。MVC-ISO（10.3±11.4%）显著（p<0.05）增加，MVC-CON(10.9±9.5%)，2/3MVC组观察到MVC-ECC(9.3±8.8%)扭矩和MT(10.1±9.2%)。这些变化与MVC组的变化没有显着差异。这些结果表明，哑铃的2/3强度偏心收缩与最大强度等速偏心收缩一样有效，可以诱导肌肉适应。
