Effects of Kilohertz-frequency and Low-frequency Current on Triceps Surae

Summary

Neuromuscular electrical Stimulation (NMES) can minimize muscle atrophy and complications related to muscle disuse and help improve neuromuscular performance. Medium and low-frequency currents have been assessed regarding the generation of evoked torque, sensory discomfort, muscle fatigue, and peripheral oxygen extraction. In addition, metabolic stress is also linked to muscle strength gain, an important aspect to be evaluated in addition to NMES physical parameters. Thus, the aim of this study is to compare the effects of different NMES protocols applied to the triceps surae muscle for evoked torque, muscle fatigue, sensory discomfort, and peripheral oxygen extraction in healthy individuals. This is a crossover, experimental, randomized, double-blind trial composed of apparently healthy participants. All NMES protocols will be tested on the same individual with randomization of the sequence of intervention protocols. There will be a total of 5 encounters with seven days between them. Session 1 will evaluate the anthropometric measures, the maximum intensity for each intervention protocol, and the sequence of intervention protocols for each individual will be randomized. Sessions 2, 3, 4, and 5 will be composed equally with the assessment of the maximum voluntary and evoked joint torque of the triceps surae muscle through the isokinetic dynamometer, evaluation of muscle fatigue through the H-reflex, M-wave, fatigue index, time-torque-integral, and recruitment curve, evaluation of peripheral oxygen extraction through NIRS (Near Infrared Spectroscopy), electromyographic signals to assessed the RMS (root mean square) and the median frequency, evaluation of the level of sensory discomfort through the Visual Analog Pain Scale and finally by the NMES protocol. The EENM protocols will be as follows: CR10% (Russian Current at 2500 Hz, modulated in 50 Hz bursts, 200 µs and 10% duty cycle - 2 ms of 18 ms bursts and interbusrts), CA10% (Aussie Current with 1000 Hz, modulated in 50 Hz bursts, 500 µs and 10% duty cycle - 2 ms of 18 ms bursts and interbusrts), CP500 (pulsed current with 50 Hz, 500 µs phase) and CP200 (Pulsed current with 50 Hz, 200 µs phase). all protocols will be performed on the triceps surae muscle.

Conditions

• Healthy

Interventions

OTHER

Russian current 10%

Russian current with 2500 Hz, modulated in bursts of 50 Hz, 200 µs and 10% duty cycle - 2 ms bursts and 18 ms interbusrts

OTHER

Aussie current 10%

Aussie current with 1000 Hz, modulated in bursts of 50 Hz, 500 µs and 10% duty cycle - 2 ms bursts and 18 ms interbusrts

OTHER

Pulsed current 500 µs phase

Pulsed current, modulated in 50 Hz, 500 µs

OTHER

Pulsed current 200 µs phase

Pulsed current, modulated in 50 Hz, 200 µs

Sponsors & Collaborators

• University of Brasilia

  lead OTHER

Principal Investigators

• João LQ Durigan, PhD · University of Brasilia

Study Design

Allocation

RANDOMIZED

Purpose

HEALTH_SERVICES_RESEARCH

Masking

DOUBLE

Model

CROSSOVER

Eligibility

Min Age

18 Years

Max Age

45 Years

Sex

ALL

Healthy Volunteers

Yes

Timeline & Regulatory

Start

2023-05-23

Primary Completion

2024-05-22

Completion

2024-05-22

Countries

• Brazil

Study Locations