Acute Effects of High-Intensity Aerobic Exercise on Motor Cortical Excitability and Inhibition in Sedentary Adults

Abstract

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%, p < 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, p = 0.002). There was a non-significant (p = 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.

Acute effects of two different work-to-rest ratio of high-intensity interval training on brain-derived neurotrophic factor in untrained young men

“…We observed that serum BDNF levels increased significantly relative to pre-exercise levels whether participants performed 1 min for 15 bouts or 2 min for 10 bouts of HIIT interventions. Which is consistent with previous study in humans ( Saucedo Marquez et al, 2015 ; Cabral-Santos et al, 2016 ; Martínez-Díaz et al, 2020 ; Tsai et al, 2021 ; Hendy et al, 2022 ). Although the training duration of the two HIIT protocols was different, with maximum levels of serum BDNF being observed toward the end of intervention.…”

“…Which is consistent with previous study in humans (Saucedo Marquez et al, 2015;Cabral-Santos et al, 2016;Martínez-Díaz et al, 2020;Tsai et al, 2021;Hendy et al, 2022). Although the training duration of the two HIIT protocols was different, with maximum levels of serum BDNF being observed toward the end of intervention.…”

Effectiveness of high‐intensity interval training on peripheral brain‐derived neurotrophic factor in adults: A systematic review and network meta‐analysis

“…According to the RoB 2.0 Cochrane tool, 24 one study scored at "low risk of bias", 55 four studies scored at "high risk of bias", 19,43,48,50 whereas the remaining 17 studies rated "some concerns" 20,[38][39][40][41][42][44][45][46][47]49,[51][52][53][54]56,57 (Figure S1). By domain, the randomization process was the highest rated as "high risk of bias" (13.6%), and the selection of the reported outcome was the highest rated as "some concerns" (81.8%).…”

“…The length of the exercise programs, in which the chronic effect of training was evaluated, ranged from 3 to 12 weeks, and the frequency ranged from 2 to 5 days per week, prevailing 3 days per week in eight studies. 19,39,[41][42][43]45,47,52 HIIT sessions were performed primarily on cycle ergometer in 10 studies, 20,[39][40][41]44,45,47,51,52,55 followed by treadmill in seven studies, 19,38,42,43,48,49,57 seated stepper in one study, 57 one study in a Speedflex machine, 56 lower body ergometer in one study, 45 different types of exercises (squat jump, inchworm, walk down-shoulder tap, plank get ups, goblet squats, jackknife crunch, and burpee mountain climbing movements) in one study 54 and various aerobic exercise equipment (e.g., treadmill, cycle ergometer, elliptical, etc.) or dance/movement-based routines in one study.…”

Improved cognitive-motor processing speed and decreased functional connectivity after high intensity aerobic exercise in individuals with chronic stroke

“…High intensity aerobic exercise in particular can also improve motor skill acquisition in neurologically intact people (Skriver et al ., 2014; Stavrinos & Coxon, 2017; Dal Maso et al ., 2018; Kendall et al ., 2020), and individuals with chronic stroke (Nepveu et al ., 2017). These improvements are linked to a decrease in the neurotransmitter gamma-aminobutyric acid (Singh et al ., 2014; Singh & Staines, 2015; Stavrinos & Coxon, 2017; Hendy et al ., 2022), and an increase in the protein brain-derived neurotrophic factor (Sleiman et al ., 2016), both of which play important roles in neuroplasticity (Stagg et al ., 2011; Mang et al ., 2013; Andreska et al ., 2020). Therefore, beyond the potential cognitive benefits associated with high intensity aerobic exercise, pairing it with motor rehabilitation is a promising method to enhance cognitive-motor function.…”