Fimland Marius S, Helgerud Jan, Gruber Markus, Leivseth Gunnar, Hoff Jan
Department of Circulation and Imaging, Norwegian University of Science and Technology, Trondheim 7489, Norway.
Eur J Appl Physiol. 2009 Sep;107(1):21-9. doi: 10.1007/s00421-009-1096-4. Epub 2009 Jun 6.
The purpose of this study was to investigate whether neural adaptations following functional multiple-joint leg press training can induce neural adaptations to the plantar flexor muscles in a single-joint contraction task. Subjects were randomised to a maximal strength training (MST) (n = 10) or a control group (n = 9). MST consisted of 24 sessions (8 weeks) of 4 x 4 repetitions of horizontal leg press using maximal intended velocity in the concentric phase with the movement ending in a plantar flexion. Neural adaptations in the soleus and gastrocnemius medialis (GM) were assessed by surface electromyographic activity and V-waves during maximum voluntary isometric contraction (MVIC), and also by H-reflexes in the soleus during rest and 20% MVIC. One repetition maximum leg press increased by 44 +/- 14% (mean +/- SD; P < 0.01). Plantar flexion MVIC increased by 20 +/- 14% (P < 0.01), accompanied by 13 +/- 19% (P < 0.05) increase in soleus, but not GM surface electromyography. Soleus V/M(SUP) increased by 53 +/- 66% and in GM by 59 +/- 64% (P < 0.05). Normalised soleus H-reflexes remained unchanged by training. No changes occurred in the control group. These results suggest that leg press MST can induce neural adaptations in a single-joint plantar flexion MVIC task.
本研究的目的是调查功能性多关节腿举训练后的神经适应性是否能在单关节收缩任务中诱导对跖屈肌的神经适应性。受试者被随机分为最大力量训练组（MST）（n = 10）或对照组（n = 9）。MST包括24节训练课（8周），采用向心阶段最大预期速度进行4组，每组4次的水平腿举训练，动作以跖屈结束。通过最大自主等长收缩（MVIC）期间的表面肌电图活动和V波评估比目鱼肌和内侧腓肠肌（GM）的神经适应性，同时在休息和20% MVIC时通过比目鱼肌的H反射进行评估。一次重复最大腿举增加了44±14%（平均值±标准差；P < 0.01）。跖屈MVIC增加了20±14%（P < 0.01），同时比目鱼肌表面肌电图增加了13±19%（P < 0.05），但GM表面肌电图未增加。比目鱼肌的V/M（SUP）增加了53±66%，GM增加了59±64%（P < 0.05）。训练后比目鱼肌标准化H反射保持不变。对照组未发生变化。这些结果表明，腿举MST可以在单关节跖屈MVIC任务中诱导神经适应性。
