Adrien Farabet1, Robin Souron1, Guillaume Y Millet2, Thomas Lapole3. 1. Univ Lyon, UJM-Saint-Etienne, Laboratoire Interuniversitaire de Biologie de la Motricité, EA 7424, F-42023, SAINT-ETIENNE, France. 2. Human Performance Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, Canada. 3. Univ Lyon, UJM-Saint-Etienne, Laboratoire Interuniversitaire de Biologie de la Motricité, EA 7424, F-42023, SAINT-ETIENNE, France. thomas.lapole@univ-st-etienne.fr.
Abstract
PURPOSE: Prolonged local vibration is known to impair muscle performance. While involved mechanisms were previously evidenced at the spinal level, changes at the cortical level were also hypothesized. The aims of the present study were to investigate the effects of 30 min of 100-Hz tibialis anterior muscle vibration on force production capacities and to further identify the respective changes in spinal loop properties, descending voluntary drive and corticospinal properties. METHODS: Thirteen subjects were tested before and after a vibration condition, and before and after a resting control condition. Maximal voluntary contraction (MVC) in dorsiflexion was measured. Transcranial magnetic stimulation was superimposed during MVCs to assess cortical voluntary activation (VATMS), motor-evoked potential amplitude (MEP) and cortical silent period length (CSP). MEP and CSP were also measured during 50 and 75 % MVC contractions. Spinal excitability was investigated by mean of H-reflex. RESULTS: There were no vibration effects on MVC (p = 0.805), maximal EMG activity (p = 0.653), VATMS (p = 1), and CSP (p = 0.877). Vibration tended to decrease MEP amplitude (p = 0.117). H-reflex amplitude was depressed following vibration (p = 0.008). CONCLUSIONS: Dorsiflexion maximal force production capacities were unaffected by 30 min of tibialis anterior muscle vibration, despite spinal loop and corticospinal excitabilities being reduced. These findings suggest that acute prolonged vibration has the potential to modulate corticospinal excitability of lower limb muscles without a concomitant functional consequence.
PURPOSE: Prolonged local vibration is known to impair muscle performance. While involved mechanisms were previously evidenced at the spinal level, changes at the cortical level were also hypothesized. The aims of the present study were to investigate the effects of 30 min of 100-Hz tibialis anterior muscle vibration on force production capacities and to further identify the respective changes in spinal loop properties, descending voluntary drive and corticospinal properties. METHODS: Thirteen subjects were tested before and after a vibration condition, and before and after a resting control condition. Maximal voluntary contraction (MVC) in dorsiflexion was measured. Transcranial magnetic stimulation was superimposed during MVCs to assess cortical voluntary activation (VATMS), motor-evoked potential amplitude (MEP) and cortical silent period length (CSP). MEP and CSP were also measured during 50 and 75 % MVC contractions. Spinal excitability was investigated by mean of H-reflex. RESULTS: There were no vibration effects on MVC (p = 0.805), maximal EMG activity (p = 0.653), VATMS (p = 1), and CSP (p = 0.877). Vibration tended to decrease MEP amplitude (p = 0.117). H-reflex amplitude was depressed following vibration (p = 0.008). CONCLUSIONS: Dorsiflexion maximal force production capacities were unaffected by 30 min of tibialis anterior muscle vibration, despite spinal loop and corticospinal excitabilities being reduced. These findings suggest that acute prolonged vibration has the potential to modulate corticospinal excitability of lower limb muscles without a concomitant functional consequence.
Entities:
Keywords:
Cortical voluntary activation; H-reflex; Transcranial magnetic stimulation; Vibration
Authors: Maja Rogić Vidaković; Ana Kostović; Ana Jerković; Joško Šoda; Mladen Russo; Maja Stella; Ante Knežić; Igor Vujović; Mario Mihalj; Jure Baban; Davor Ljubenkov; Marin Peko; Benjamin Benzon; Maximilian Vincent Hagelien; Zoran Đogaš Journal: Med Sci Monit Date: 2020-05-27
Authors: Robin Souron; Thibault Besson; Chris J McNeil; Thomas Lapole; Guillaume Y Millet Journal: Front Hum Neurosci Date: 2017-10-25 Impact factor: 3.169