Noguchi Takanori, Demura Shinichi, Takahashi Kenji, Demura Gou, Mori Yasunori
1Fukui University of Technology, Fukui, Japan; 2Graduate School of Natural Science & Techology, Kanazawa University, Ishikawa, Japan; 3Teikyo Heisei University, Chiba, Japan; 4Tagami Orthopedic Clinic, Ishikawa, Japan; and 5The United Graduate School of Professional Teacher Education, Kyoto, Japan.
J Strength Cond Res. 2014 Jan;28(1):82-6. doi: 10.1519/JSC.0b013e3182909112.
We examined the differences in muscle power between the dominant and nondominant upper limbs of 33 healthy, right-handed, university baseball players (mean age, 20.4 ± 1.1 years) with an average baseball experience >11 years. After measuring maximal voluntary contraction (MVC) of hand grip, elbow flexion, and shoulder internal rotation in both upper limbs, the muscle power of each joint was measured at 40%, 50%, and 60% MVC. No significant differences were observed in the main factors affecting MVC and elbow flexion power loads between dominant and nondominant upper limbs. For handgrip power, load factors at 40% MVC in the dominant hand were lower than those at 60% MVC in the same hand and those at 50% and 60% MVC in the nondominant hand. Significant differences were observed in shoulder internal rotation power between dominant and nondominant upper limbs, with the dominant limb having greater power at all loads. Correlations between muscle power of both upper limbs for handgrip and elbow flexion were significant and moderately high at all loads. For shoulder internal rotation power, the degree of correlation was significant and moderately high at 40% MVC but low to moderate at 50% and 60% MVC. Therefore, baseball players have marked lateral dominance in shoulder internal rotation power unlike handgrip and elbow flexion power, although the relationship between shoulder internal rotation muscle powers of both upper limbs becomes lower with increasing load. The dominance of muscle power of each joint varied even in the same upper limb. It is thus beneficial for baseball players to train with even loads on both arms or adopt simultaneous workout of both arms after adjusting for strength differences.
我们研究了33名健康的右利手大学棒球运动员（平均年龄20.4±1.1岁，平均棒球经验超过11年）优势上肢和非优势上肢之间的肌肉力量差异。在测量了双上肢的握力、肘屈曲和肩内旋的最大自主收缩（MVC）后，在40%、50%和60%MVC时测量了每个关节的肌肉力量。在影响MVC和肘屈曲力量负荷的主要因素方面，优势上肢和非优势上肢之间未观察到显著差异。对于握力，优势手在40%MVC时的负荷因子低于同一手在60%MVC时的负荷因子以及非优势手在50%和60%MVC时的负荷因子。优势上肢和非优势上肢之间的肩内旋力量存在显著差异，优势肢体在所有负荷下的力量都更大。双上肢握力和肘屈曲的肌肉力量在所有负荷下的相关性均显著且中等偏高。对于肩内旋力量，在40%MVC时相关性程度显著且中等偏高，但在50%和60%MVC时为低到中等。因此，与握力和肘屈曲力量不同，棒球运动员在肩内旋力量方面存在明显的侧方优势，尽管双上肢肩内旋肌肉力量之间的关系随着负荷增加而降低。即使在同一上肢中，每个关节的肌肉力量优势也有所不同。因此，对于棒球运动员来说，在调整力量差异后，双臂进行均匀负荷训练或同时进行双臂训练是有益的。
