Paraschos I, Hassani A, Bassa E, Hatzikotoulas K, Patikas D, Kotzamanidis C
Physical Education and Sports Sciences, Aristotle University, Thessaloniki, Greece.
Int J Sports Med. 2007 Nov;28(11):958-63. doi: 10.1055/s-2007-964984. Epub 2007 May 11.
The purpose of the present study was to investigate the differences in neuromuscular activation of agonist and antagonist muscles between men and prepubertal boys during a maximal isokinetic fatigue test. Ten prepubertal boys (mean +/- SD age: 10.5 +/- 0.6 years) and fourteen adults (age: 24.3 +/- 2.5 years) executed 25 consecutive maximal isokinetic knee extensions at 60 deg . s (-1). Peak torque and the electromyogram (EMG) of the vastus lateralis, vastus medialis and biceps femoris muscles were recorded. During the fatigue protocol, the prepubertal boys were able to produce higher torque than the adults, when expressed as percent of their maximal value, indicating that adults were more fatigable. The agonist activity, especially for the vastus lateralis muscle, increased in both groups during the first 10 knee extensions, and then decreased more in adults. The antagonist activity of biceps femoris muscle in adults remained constant throughout the fatigue task, whereas the children showed, on average, an increased biceps femoris antagonistic activation, especially during the first 10 and last 5 knee extensions. These results suggest that adults are more fatigable than children during a maximal isokinetic fatigue protocol, probably due to an increased inhibition or reduced facilitation of their agonist drive.
本研究的目的是调查在最大等速疲劳试验期间，青春期前男孩与成年男性之间，主动肌和拮抗肌神经肌肉激活的差异。十名青春期前男孩（平均±标准差年龄：10.5±0.6岁）和十四名成年人（年龄：24.3±2.5岁）以60度·秒⁻¹的速度连续进行25次最大等速膝关节伸展。记录股外侧肌、股内侧肌和股二头肌的峰值扭矩和肌电图（EMG）。在疲劳试验过程中，以各自最大值的百分比表示时，青春期前男孩能够产生比成年人更高的扭矩，表明成年人更容易疲劳。在最初的10次膝关节伸展过程中，两组的主动肌活动，尤其是股外侧肌的活动均增加，然后成年人的下降幅度更大。在整个疲劳任务中，成年人股二头肌的拮抗肌活动保持不变，而儿童平均表现出股二头肌拮抗肌激活增加，尤其是在最初的10次和最后的5次膝关节伸展过程中。这些结果表明，在最大等速疲劳试验中，成年人比儿童更容易疲劳，这可能是由于他们主动肌驱动的抑制增加或易化减少所致。
