Wood L E, Dixon S, Grant C, Armstrong N
Sport and Exercise Science, University of Portsmouth, Portsmouth, United Kingdom.
Int J Sports Med. 2008 Jun;29(6):466-70. doi: 10.1055/s-2007-989234. Epub 2007 Nov 14.
The aim of this study was to examine age and gender differences in isokinetic eccentric (ECC) elbow flexion (EF) and extension (EE) torques in children. Thirty-seven children participated in a 3-year longitudinal study. The average age +/- SD at the first test occasion was 13.0 +/- 0.3 years. Isokinetic ECC EF and EE torques at 0.52 rad . s (-1), MRI determined muscle cross-sectional areas (CSAs), stature, and arm length were determined annually. Concentric (CON) EF and EE torques for the same children reported previously, enabled functional torque ratios (ECC antagonist/CON agonist) to be calculated [ ]. In contrast to isokinetic EF torques, ECC EE torques were not significantly higher than CON EE torques (across test occasions and for boys and girls). Functional torque ratios did not significantly differ with age or between boys and girls. Multilevel modelling was used to examine age and gender effects once differences in body/muscle size had been considered. ECC EF torque was relatively greater in girls following adjustment for size. These data contribute to the understanding of differences in upper body strength performance and injury propensity during growth and maturation, suggesting CON and ECC torque development are muscle and gender specific.
本研究的目的是探讨儿童等速离心（ECC）时肘关节屈曲（EF）和伸展（EE）扭矩的年龄和性别差异。37名儿童参与了一项为期3年的纵向研究。首次测试时的平均年龄±标准差为13.0±0.3岁。每年测定0.52弧度·秒（-1）时的等速ECC EF和EE扭矩、MRI测定的肌肉横截面积（CSA）、身高和臂长。根据先前报道的同一批儿童的向心（CON）EF和EE扭矩，能够计算出功能扭矩比（ECC拮抗剂/CON激动剂）[ ]。与等速EF扭矩相反，ECC EE扭矩并不显著高于CON EE扭矩（在各测试阶段以及男孩和女孩中均如此）。功能扭矩比在年龄方面以及男孩和女孩之间没有显著差异。在考虑了身体/肌肉大小差异后，使用多水平模型来检验年龄和性别效应。在对大小进行调整后，女孩的ECC EF扭矩相对更大。这些数据有助于理解生长和成熟过程中上身力量表现和受伤倾向的差异，表明CON和ECC扭矩的发展具有肌肉和性别特异性。
