Hendy Ashlee M, Andrushko Justin W, Della Gatta Paul A, Teo Wei-Peng
Faculty of Health, School of Exercise and Nutrition Sciences, Institute for Physical Activity and Nutrition (IPAN), Deakin University, Geelong, VIC, Australia.
Brain Behaviour Laboratory, Department of Physical Therapy, Faculty of Medicine, The University of British Columbia, Vancouver, BC, Canada.
Front Psychol. 2022 Mar 17;13:814633. doi: 10.3389/fpsyg.2022.814633. eCollection 2022.
Transcranial magnetic stimulation studies have demonstrated increased cortical facilitation and reduced inhibition following aerobic exercise, even when examining motor regions separate to the exercised muscle group. These changes in brain physiology following exercise may create favorable conditions for adaptive plasticity and motor learning. One candidate mechanism behind these benefits is the increase in brain-derived neurotropic factor (BDNF) observed following exercise, which can be quantified from a venous blood draw. The aim of this study was to investigate changes in motor cortex excitability and inhibition of the upper limb, and circulating BDNF, following high-intensity interval training (HIIT) on a stationary bicycle. Nineteen sedentary adults participated in a randomized crossover design study involving a single bout of high-intensity interval cycling for 20 min or seated rest. Venous blood samples were collected, and transcranial magnetic stimulation (TMS) was used to stimulate the extensor carpi radialis (ECR), where motor evoked potentials (MEP) were recorded pre- and post-condition. Following exercise, there was a significant increase (29.1%, < 0.001) in corticospinal excitability measured at 120% of resting motor threshold (RMT) and a reduction in short-interval cortical inhibition (SICI quantified as 86.2% increase in the SICI ratio, = 0.002). There was a non-significant ( = 0.125) 23.6% increase in BDNF levels. Collectively, these results reflect a net reduction in gamma aminobutyric acid (GABA)ergic synaptic transmission and increased glutamatergic facilitation, resulting in increased corticospinal excitability. This study supports the notion that acute high-intensity exercise provides a potent stimulus for inducing cortical neuroplasticity, which may support enhanced motor learning.
经颅磁刺激研究表明，有氧运动后皮质易化增加且抑制减少，即使在检查与运动肌肉群分开的运动区域时也是如此。运动后大脑生理学的这些变化可能为适应性可塑性和运动学习创造有利条件。这些益处背后的一个潜在机制是运动后观察到的脑源性神经营养因子（BDNF）增加，这可以通过静脉采血进行量化。本研究的目的是调查在固定自行车上进行高强度间歇训练（HIIT）后上肢运动皮质兴奋性和抑制以及循环BDNF的变化。19名久坐不动的成年人参与了一项随机交叉设计研究，其中包括单次20分钟的高强度间歇骑行或坐着休息。采集静脉血样本，并使用经颅磁刺激（TMS）刺激桡侧腕伸肌（ECR），在实验前后记录运动诱发电位（MEP）。运动后，在静息运动阈值（RMT）的120%时测量的皮质脊髓兴奋性显著增加（29.1%，<0.001），短间隔皮质抑制减少（SICI量化为SICI比率增加86.2%，=0.002）。BDNF水平有23.6%的非显著性增加（=0.125）。总体而言，这些结果反映了γ-氨基丁酸（GABA）能突触传递的净减少和谷氨酸能易化增加，导致皮质脊髓兴奋性增加。本研究支持这样一种观点，即急性高强度运动为诱导皮质神经可塑性提供了有力刺激，这可能有助于增强运动学习。
