Weir J P, Housh T J, Weir L L
Center for Youth Fitness and Sports Research, University of Nebraska-Lincoln 68588-0229.
J Appl Physiol (1985). 1994 Jul;77(1):197-201. doi: 10.1152/jappl.1994.77.1.197.
The purpose of this study was to examine the effects of unilateral strength training on the strength and integrated electromyogram (IEMG) of the trained and untrained limbs at several joint angles. A training group [TRN; 4 females and 3 males, age 22 +/- 4 yr (SD)] exercised for 6 wk with isometric leg extensions at 80% of maximal isometric torque. A control group (3 females and 3 males, age 24 +/- 4 yr) did not exercise. The training was performed three times per week at 0.79 rad below the horizontal plane. The subjects were tested at joint angles of 0.00, 0.26, 0.79, 1.31, and 1.57 rad. Bipolar surface electrodes were used to record the IEMG of the vastus lateralis. The results indicated a cross-training effect and joint angle specificity for isometric torque in TRN only, with significant (P < 0.0005) increases in torque (collapsed across limb) at 0.26 (23.3%) and 0.79 (22.3%) rad. There was a dissociation, however, between changes in torque and IEMG with an increase (P < 0.05) in IEMG (collapsed across limb and angle) for TRN. The dissociation between the IEMG and strength changes was possibly due to differential responses to training in the four muscles of the quadriceps femoris.
本研究的目的是在多个关节角度下，考察单侧力量训练对训练侧和未训练侧肢体力量及积分肌电图（IEMG）的影响。一个训练组[TRN；4名女性和3名男性，年龄22±4岁（标准差）]进行为期6周的等长伸腿训练，强度为最大等长扭矩的80%。一个对照组（3名女性和3名男性，年龄24±4岁）不进行训练。训练每周进行3次，在水平面以下0.79弧度处进行。在0.00、0.26、0.79、1.31和1.57弧度的关节角度对受试者进行测试。使用双极表面电极记录股外侧肌的IEMG。结果表明，仅在TRN组中存在交叉训练效应和等长扭矩的关节角度特异性，在0.26（23.3%）和0.79（22.3%）弧度处，扭矩（双侧合并）显著增加（P<0.0005）。然而，对于TRN组，扭矩变化与IEMG之间存在分离，IEMG（双侧和各角度合并）增加（P<0.05）。IEMG与力量变化之间的分离可能是由于股四头肌四块肌肉对训练的不同反应所致。
