Key Laboratory of Exercise and Health Sciences of Ministry of Education, Shanghai University of Sport, Shanghai, 200438, China.
School of Exercise and Health, Shanghai University of Sport, Shanghai, 200438, China.
J Neuroeng Rehabil. 2024 Mar 20;21(1):38. doi: 10.1186/s12984-024-01336-7.
Temporal interference (TI) stimulation, an innovative non-invasive brain stimulation technique, has the potential to activate neurons in deep brain regions. The objective of this study was to evaluate the effects of repetitive TI stimulation targeting the lower limb motor control area (i.e., the M1 leg area) on lower limb motor function in healthy individuals, which could provide evidence for further translational application of non-invasive deep brain stimulation.
In this randomized, double-blinded, parallel-controlled trial, 46 healthy male adults were randomly divided into the TI or sham group. The TI group received 2 mA (peak-to-peak) TI stimulation targeting the M1 leg area with a 20 Hz frequency difference (2 kHz and 2.02 kHz). Stimulation parameters of the sham group were consistent with those of the TI group but the current input lasted only 1 min (30 s ramp-up and ramp-down). Both groups received stimulation twice daily for five consecutive days. The vertical jump test (countermovement jump [CMJ], squat jump [SJ], and continuous jump [CJ]) and Y-balance test were performed before and after the total intervention session. Two-way repeated measures ANOVA (group × time) was performed to evaluate the effects of TI stimulation on lower limb motor function.
Forty participants completed all scheduled study visits. Two-way repeated measures ANOVA showed significant group × time interaction effects for CMJ height (F = 8.858, p = 0.005) and SJ height (F = 6.523, p = 0.015). The interaction effect of the average CJ height of the first 15 s was marginally significant (F = 3.550, p = 0.067). However, there was no significant interaction effect on the Y balance (p > 0.05). Further within-group comparisons showed a significant post-intervention increase in the height of the CMJ (p = 0.004), SJ (p = 0.010) and the average CJ height of the first 15 s (p = 0.004) in the TI group.
Repetitive TI stimulation targeting the lower limb motor control area effectively increased vertical jump height in healthy adult males but had no significant effect on dynamic postural stability.
时间干扰（TI）刺激是一种创新的非侵入性脑刺激技术，具有激活深部脑区神经元的潜力。本研究旨在评估针对下肢运动控制区（即 M1 腿部区域）的重复 TI 刺激对健康个体下肢运动功能的影响，为进一步转化应用非侵入性深部脑刺激提供证据。
在这项随机、双盲、平行对照试验中，将 46 名健康成年男性随机分为 TI 组或假刺激组。TI 组接受 2 mA（峰峰值）、20 Hz 频率差（2 kHz 和 2.02 kHz）的针对 M1 腿部区域的 TI 刺激。假刺激组的刺激参数与 TI 组一致，但电流输入仅持续 1 分钟（30 秒上升和下降）。两组均每天接受两次刺激，连续 5 天。在总干预疗程前后进行垂直跳跃测试（反跳式垂直跳跃[CMJ]、深蹲跳跃[SJ]和连续跳跃[CJ]）和 Y 平衡测试。采用双因素重复测量方差分析（组×时间）评估 TI 刺激对下肢运动功能的影响。
40 名参与者完成了所有计划的研究访问。双因素重复测量方差分析显示，CMJ 高度（F=8.858，p=0.005）和 SJ 高度（F=6.523，p=0.015）的组×时间交互作用有显著差异。前 15 秒平均 CJ 高度的交互作用效应接近显著（F=3.550，p=0.067）。然而，Y 平衡测试没有显著的交互作用（p>0.05）。进一步的组内比较显示，TI 组干预后 CMJ（p=0.004）、SJ（p=0.010）和前 15 秒平均 CJ 高度（p=0.004）显著增加。
针对下肢运动控制区的重复 TI 刺激可有效提高健康成年男性的垂直跳跃高度，但对动态姿势稳定性无显著影响。
