Effects of High-Definition Transcranial Direct Current Stimulation on Excitability of Spinal Motoneurons under Ankle Dorsi-Plantarflexion Fatigue Task
10.16156/j.1004-7220.2024.02.015
- VernacularTitle:高精度经颅直流电刺激对踝关节跖背屈疲劳任务中脊髓运动神经元兴奋性的影响
- Author:
Changxiao YU
1
,
2
;
Jianglong ZHAN
;
Bin SHEN
;
Junhong ZHOU
;
Linfeng XU
;
Weijie FU
Author Information
1. 杭州医学院康复学院,杭州 310000
2. 上海体育大学运动健身科技省部共建教育部重点实验室,上海 200438
- Keywords:
high-definition transcranial direct current stimulation(HD-tDCS);
maximal voluntary isometric contraction(MVIC);
neural impulses;
corticospinal pathway;
α-motoneuron activity;
muscle fatigue
- From:
Journal of Medical Biomechanics
2024;39(2):293-298
- CountryChina
- Language:Chinese
-
Abstract:
Objective To investigate the effects of high-definition transcranial direct current stimulation(HD-tDCS)on the modulation of the H-reflex and M-wave during ankle dorsiflexion-plantar flexion fatigue tasks to provide direction for the application of HD-tDCS in mitigating neuromuscular fatigue.Methods Twenty healthy young male participants were recruited and randomly assigned to either the real stimulation or sham stimulation group,with 10 participants in each group.The intervention consisted of a 5-day single-blind HD-tDCS application(duration:20 min;intensity:2 mA;target:Cz).Baseline measurements of the H-reflex and M-wave under resting conditions,M-wave during maximal voluntary isometric contraction(MVIC)of the dorsiflexor muscle,and MVIC torque of the dorsiflexor and plantar flexor muscles were obtained.An ankle dorsiflexion fatigue task was performed to determine the time to achieve fatigue for the task.The same fatigue task was repeated and evaluated one day after the intervention.A repeated-measures two-factor(stimulation condition x pre/post fatigue)analysis of variance(ANOVA)was used to analyze the effects of independent variables on the mechanical properties of the muscles and α-motoneuron conduction characteristics.Results After fatigue,voluntary activation(VA),maximal H-reflex(Hmax),maximal M-wave(Mmax),and dorsiflexor and plantar flexor MVIC torques in both groups were significantly reduced compared with pre-fatigue levels(P＜0.05).However,compared to the real stimulation group,the sham stimulation group showed a more significant decline in VA and plantar flexor MVIC torque(P＜0.05).Conclusions A continuous 5-day HD-tDCS intervention can effectively increase α-motoneuron activity at the spinal segment.It can also exert an inhibitory effect on reducing information transmission capacity at the peripheral neuromuscular junction under the ankle dorsi-plantarflexion fatigue task.
