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Promoting Motor Cortical Plasticity with Acute Aerobic Exercise: A Role for Cerebellar Circuits.

Mang CS, Brown KE, Neva JL, Snow NJ, Campbell KL, Boyd LA - Neural Plast. (2016)

Bottom Line: Here, we investigated the effect of acute aerobic exercise on cerebellar circuits, and their potential contribution to altered M1 plasticity in healthy individuals (age: 24.8 ± 4.1 years).In Experiment   1, acute aerobic exercise reduced cerebellar inhibition (CBI) (n = 10, p = 0.01), elicited by dual-coil paired-pulse transcranial magnetic stimulation.Thus, the results of these planned comparisons indirectly provide modest evidence that modulation of cerebellar circuits may contribute to exercise-induced increases in M1 plasticity.

View Article: PubMed Central - PubMed

Affiliation: Graduate Program in Rehabilitation Sciences, Faculty of Medicine, University of British Columbia, Vancouver, BC, Canada V6T 1Z3.

ABSTRACT
Acute aerobic exercise facilitated long-term potentiation-like plasticity in the human primary motor cortex (M1). Here, we investigated the effect of acute aerobic exercise on cerebellar circuits, and their potential contribution to altered M1 plasticity in healthy individuals (age: 24.8 ± 4.1 years). In Experiment   1, acute aerobic exercise reduced cerebellar inhibition (CBI) (n = 10, p = 0.01), elicited by dual-coil paired-pulse transcranial magnetic stimulation. In Experiment   2, we evaluated the facilitatory effects of aerobic exercise on responses to paired associative stimulation, delivered with a 25 ms (PAS25) or 21 ms (PAS21) interstimulus interval (n = 16 per group). Increased M1 excitability evoked by PAS25, but not PAS21, relies on trans-cerebellar sensory pathways. The magnitude of the aerobic exercise effect on PAS response was not significantly different between PAS protocols (interaction effect: p = 0.30); however, planned comparisons indicated that, relative to a period of rest, acute aerobic exercise enhanced the excitatory response to PAS25 (p = 0.02), but not PAS21 (p = 0.30). Thus, the results of these planned comparisons indirectly provide modest evidence that modulation of cerebellar circuits may contribute to exercise-induced increases in M1 plasticity. The findings have implications for developing aerobic exercise strategies to "prime" M1 plasticity for enhanced motor skill learning in applied settings.

No MeSH data available.


Related in: MedlinePlus

Overview of experimental procedures for Experiment   1 (a) and Experiment   2 (b). Each session was approximately two hours in duration. CBI: cerebellar inhibition; MEP: motor evoked potential; PAS25: paired associative stimulation with 25 ms interstimulus interval; PAS21: paired associative stimulation with 21 ms interstimulus interval.
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fig1: Overview of experimental procedures for Experiment   1 (a) and Experiment   2 (b). Each session was approximately two hours in duration. CBI: cerebellar inhibition; MEP: motor evoked potential; PAS25: paired associative stimulation with 25 ms interstimulus interval; PAS21: paired associative stimulation with 21 ms interstimulus interval.

Mentions: This study consisted of two separate experiments designed to evaluate the potential impact of acute high-intensity cycling on M1-cerebellar circuits for a nonexercised muscle of the hand (abductor pollicis brevis, APB). Prior to participation in experimental sessions, each participant completed a graded maximal exercise test, for the purpose of subsequent exercise intensity prescription. For “Experiment   1,” participants completed one single session to evaluate the impact of a standardized bout of high-intensity interval cycling on CBI. The session involved an assessment of CBI at three time points: baseline, immediately following 20 minutes of seated rest (preexercise), and immediately following a 20-minute high-intensity aerobic exercise interval session (after exercise). Thirteen individuals participated in this experiment; however, the session was not completed in three participants due to a lack of CBI at the baseline time point (n = 2) and discomfort with cerebellar stimulation (n = 1). Thus, the final dataset included a total of 10 participants. For “Experiment   2,” 32 participants completed two sessions designed to assess the potential effects of the same high-intensity interval cycling bout on change in corticospinal excitability evoked by PAS. The experimental sessions included (1) rest followed by PAS and (2) aerobic exercise followed by PAS. Half of the participants (n = 16) underwent the experiments with PAS25 and the other half underwent PAS21. PAS groups were similar in terms of age, sex, cardiorespiratory fitness, and physical activity levels (Table 1). Session order was pseudo-randomized and performed at the same time of day (±2 hours) for each participant to account for diurnal fluctuations in M1 excitability [19]. Of the 32 participants involved in Experiment   2, 11 also participated in Experiment   1. On all testing days, participants were instructed to refrain from any exercise besides that involved in the experimental sessions. All sessions conducted on the same individuals were separated by at least 48 hours. The procedures are depicted in their experimental order in Figure 1.


Promoting Motor Cortical Plasticity with Acute Aerobic Exercise: A Role for Cerebellar Circuits.

Mang CS, Brown KE, Neva JL, Snow NJ, Campbell KL, Boyd LA - Neural Plast. (2016)

Overview of experimental procedures for Experiment   1 (a) and Experiment   2 (b). Each session was approximately two hours in duration. CBI: cerebellar inhibition; MEP: motor evoked potential; PAS25: paired associative stimulation with 25 ms interstimulus interval; PAS21: paired associative stimulation with 21 ms interstimulus interval.
© Copyright Policy - open-access
Related In: Results  -  Collection

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getmorefigures.php?uid=PMC4834415&req=5

fig1: Overview of experimental procedures for Experiment   1 (a) and Experiment   2 (b). Each session was approximately two hours in duration. CBI: cerebellar inhibition; MEP: motor evoked potential; PAS25: paired associative stimulation with 25 ms interstimulus interval; PAS21: paired associative stimulation with 21 ms interstimulus interval.
Mentions: This study consisted of two separate experiments designed to evaluate the potential impact of acute high-intensity cycling on M1-cerebellar circuits for a nonexercised muscle of the hand (abductor pollicis brevis, APB). Prior to participation in experimental sessions, each participant completed a graded maximal exercise test, for the purpose of subsequent exercise intensity prescription. For “Experiment   1,” participants completed one single session to evaluate the impact of a standardized bout of high-intensity interval cycling on CBI. The session involved an assessment of CBI at three time points: baseline, immediately following 20 minutes of seated rest (preexercise), and immediately following a 20-minute high-intensity aerobic exercise interval session (after exercise). Thirteen individuals participated in this experiment; however, the session was not completed in three participants due to a lack of CBI at the baseline time point (n = 2) and discomfort with cerebellar stimulation (n = 1). Thus, the final dataset included a total of 10 participants. For “Experiment   2,” 32 participants completed two sessions designed to assess the potential effects of the same high-intensity interval cycling bout on change in corticospinal excitability evoked by PAS. The experimental sessions included (1) rest followed by PAS and (2) aerobic exercise followed by PAS. Half of the participants (n = 16) underwent the experiments with PAS25 and the other half underwent PAS21. PAS groups were similar in terms of age, sex, cardiorespiratory fitness, and physical activity levels (Table 1). Session order was pseudo-randomized and performed at the same time of day (±2 hours) for each participant to account for diurnal fluctuations in M1 excitability [19]. Of the 32 participants involved in Experiment   2, 11 also participated in Experiment   1. On all testing days, participants were instructed to refrain from any exercise besides that involved in the experimental sessions. All sessions conducted on the same individuals were separated by at least 48 hours. The procedures are depicted in their experimental order in Figure 1.

Bottom Line: Here, we investigated the effect of acute aerobic exercise on cerebellar circuits, and their potential contribution to altered M1 plasticity in healthy individuals (age: 24.8 ± 4.1 years).In Experiment   1, acute aerobic exercise reduced cerebellar inhibition (CBI) (n = 10, p = 0.01), elicited by dual-coil paired-pulse transcranial magnetic stimulation.Thus, the results of these planned comparisons indirectly provide modest evidence that modulation of cerebellar circuits may contribute to exercise-induced increases in M1 plasticity.

View Article: PubMed Central - PubMed

Affiliation: Graduate Program in Rehabilitation Sciences, Faculty of Medicine, University of British Columbia, Vancouver, BC, Canada V6T 1Z3.

ABSTRACT
Acute aerobic exercise facilitated long-term potentiation-like plasticity in the human primary motor cortex (M1). Here, we investigated the effect of acute aerobic exercise on cerebellar circuits, and their potential contribution to altered M1 plasticity in healthy individuals (age: 24.8 ± 4.1 years). In Experiment   1, acute aerobic exercise reduced cerebellar inhibition (CBI) (n = 10, p = 0.01), elicited by dual-coil paired-pulse transcranial magnetic stimulation. In Experiment   2, we evaluated the facilitatory effects of aerobic exercise on responses to paired associative stimulation, delivered with a 25 ms (PAS25) or 21 ms (PAS21) interstimulus interval (n = 16 per group). Increased M1 excitability evoked by PAS25, but not PAS21, relies on trans-cerebellar sensory pathways. The magnitude of the aerobic exercise effect on PAS response was not significantly different between PAS protocols (interaction effect: p = 0.30); however, planned comparisons indicated that, relative to a period of rest, acute aerobic exercise enhanced the excitatory response to PAS25 (p = 0.02), but not PAS21 (p = 0.30). Thus, the results of these planned comparisons indirectly provide modest evidence that modulation of cerebellar circuits may contribute to exercise-induced increases in M1 plasticity. The findings have implications for developing aerobic exercise strategies to "prime" M1 plasticity for enhanced motor skill learning in applied settings.

No MeSH data available.


Related in: MedlinePlus