Novel perspective on contractile properties and intensity-dependent verification of force-frequency relationship during neuromuscular electrical stimulation

© 2020 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of The Physiological Society and the American Physiological Society..

PURPOSE: The aims of the present study were: (a) to examine the effect of the stimulus intensity on force-frequency and torque fluctuation-frequency relationships during Neuromuscular electrical stimulation; and (b) to identify a novel parameter that can be used to evaluate muscle contractile properties.

METHODS: Electrically elicited joint torque involving the quadriceps femoris muscle was recorded during neuromuscular electrical stimulation at two different stimulus intensities in 19 healthy men. Stimulation frequencies were set at 5-40 Hz with a duration of 10 s. Evoked joint torque was compared among all stimulation frequencies between the two stimulus intensities (68 and 113 V). The torque fluctuation at each stimulation frequency as the change in the contraction pattern was also compared between the intensities. Torque and torque fluctuation were normalized at each frequency by the largest torque or torque fluctuation, respectively. We extracted a novel parameter: the arrival point of tetanic contraction based on force-frequency and torque fluctuation-frequency curves.

RESULTS: There were significant differences in normalized torque at 5-25 and 40 Hz and in normalized torque fluctuation at 15-30 and 40 Hz between the two stimulus intensities. Extracted parameters showed no significant difference between the intensities.

CONCLUSION: The results suggest that force-frequency relationships during neuromuscular electrical stimulation are influenced by the intensity of stimulation applied to the quadriceps femoris muscle. However, we consider that it is possible to simultaneously evaluate contractile properties using the novel parameter.

Medienart:

E-Artikel

Erscheinungsjahr:

2020

Erschienen:

2020

Enthalten in:

Zur Gesamtaufnahme - volume:8

Enthalten in:

Physiological reports - 8(2020), 22 vom: 05. Nov., Seite e14598

Sprache:

Englisch

Beteiligte Personen:

Tomita, Aya [VerfasserIn]
Kawade, Shuhei [VerfasserIn]
Moritani, Toshio [VerfasserIn]
Watanabe, Kohei [VerfasserIn]

Links:

Volltext

Themen:

Contractile properties
Journal Article
Neuromuscular electrical stimulation
Research Support, Non-U.S. Gov't
Stimulus frequency
Stimulus intensity

Anmerkungen:

Date Completed 27.09.2021

Date Revised 30.03.2024

published: Print

Citation Status MEDLINE

doi:

10.14814/phy2.14598

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM317978799