Clinical trial NCT03340337: Electrical Stimulation With Different Currents: the Effects on Force, Tolerance and Fatigue in Healthy Subjects
Official title: Effects on Isometric Force Induction, Tolerance and Fatigue of Burst-modulated Kilohertz Frequency (Neo-Russian and Aussie) and Low Frequency (Rectangular Biphasic Symmetrical) Neuromuscular Electrical Stimulation in Healthy Subjects
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Healthy
Keywords: electrical stimulation
Muscle Strength
Fatigue
assessments, pain
Lead sponsor: Instituto Universitario de Ciencias de la Salud Fundación H.A. Barceló
Sponsor class: OTHER
First posted: 2017-11-13
Enrollment: 30
Sex: MALE
Minimum age (years): 18
Maximum age (years): 30
Standard ages: ADULT
Accepts healthy volunteers: yes
Allocation: RANDOMIZED
Intervention model: CROSSOVER
Intervention model description: Thirty male subjects, right leg dominant, will receive 3 types of electrical stimulation in a randomized order. Aussie current will be delivered by Aussie Sport (Ibramed) device, Neo-Russian by Neurodyn III (Ibramed) device and RBS by a Genesy (Globus) device.

MVIC and MEIC will be measured with an isometric dynamometer (3 reps x 5 sec work x 120 sec rest). The best rep will be used. Whenever the third one was the best, additional measurements will be taken until a decrease in torque will be obtained to determine the maximum. MVIC will be used for data normalization.

The VAS will be used to assess tolerance to each treatment. A ratio between MEIC and VAS will be calculated.

One week later, subjects will receive, ramdomly, a fatigue protocol with the three types of electrical stimulation that consists in 21 reps (5 sec work x 5 sec rest). The data will be normalized with the MVIC and the reps equal or below 50 % of the first rep will be considered as a fatigue rep.
Primary purpose: BASIC_SCIENCE

Brief summary: Muscle strength is the amount of force generated by muscle contraction. It could be measured with an isometric dynamometer. This is a validated tool that could be used to measure Maximal Voluntary Isometric Contraction (MVIC) and Maximal Electrical Induced Contraction (MEIC). It is claimed that higher MEIC values will result in more force gained.

If a current is more tolerated it will be easier to achieve better MEIC values. Tolerance to an electrical stimulation could be measured with the Visual Analogue Scale (VAS). A ratio between Normalized MEIC / VAS is often used, implying that the current is better with a higher ratio.

Muscle fatigue is defined as a temporary loss or decrease in force-generating ability due to previous contractions. It is claimed that medium frequency neuromuscular electrical stimulation (NMES) generates more fatigue than low frequency currents.

Aussie is a medium-frequency alternating current, sinusoidal waveform, 1 KHz carrier frequency.

Neo-Russian is a medium-frequency current, rectangular biphasic symmetrical waveform, 2,5 KHz carrier frequency.

Rectangular Biphasic symmetrical (RBS) waveform is a type of Low Pulsed Current (LPC), claimed to be better than classical Russian Current.

Purpose:

As it has been claimed that LPC is better in MEIC and tolerance, the aim of this study is to compare it with two newer medium frequency currents in terms of MEIC, tolerance and fatigue.

Methods:

Thirty male subjects, right leg dominant, will receive randomly the 3 types of electrical stimulation. Before that, the MVIC will be measured for data normalization.

The MVIC and MEIC will be measured with an isometric dynamometer. In both measurements, subjects will be asked to perform three reps (5 sec work x 120 sec rest) and the best one will be used. Whenever the third one was the best, additional measurements will be taken until a decrease in torque will be obtained to determine the maximum.

To apply Aussie electrical stimulation, an Aussie Sport (Ibramed) will be used. To apply Neo-Russian, a Neurodyn III (Ibramed) will be used. To apply RBS, a Genesy (Globus) will be used.

The VAS will be used to assess tolerance to each treatment. One week later, the subjects will receive, randomly, a fatigue protocol that consists in 21 reps (5 sec work x 5 sec rest) of electrical stimulation with the three types of current. The data will be normalized with the MVIC and the reps equal or below 50 % of the first rep will be considered as a fatigue rep.


Eligibility criteria: Inclusion Criteria:

* Healthy volunteers
* Male
* Right leg dominant
* Exercising regularly

Exclusion Criteria:

* History of injuries in the right leg
* Skin lesions
* Having a pacemaker
* Having a cardiovascular disease.
* Having a neurological disorder.
* Exercise 72 h before the procedure.

Primary outcomes:
measure: Maximal Voluntary Isometric Contraction (MVIC)
timeFrame: MVIC was measured at the beggining of the research, on Day 1. Assessed in an average of 7 min
measure: Maximal Electrical Induced Contraction (MEIC)
timeFrame: MEIC was measured on Day 1. Order: MVIC - Rest: 120 sec. - MEIC current 1 - Rest: 120 sec. - MEIC current 2 - Rest: 120 sec. - MEIC current 3 - Rest: 120 sec. - Assessed in an average of 21 min.
measure: Visual Analogue Scale (VAS)
timeFrame: Asked after evaluation of MEIC wiht each type of current. VAS current 1 - VAS current 2 - VAS current 3 - Assessed in average of 15 seconds for each current.
Secondary outcomes:
measure: Fatigue
timeFrame: Washout: 1 Week. Fatigue current 1 - Rest: 120 sec. - Fatigue current 2 - Rest: 120 sec. - Fatigue current 3 - Assessed in an average of 21 min.
Other outcomes:
Locations:
city: Ciudad Autónoma de Buenos Aire
country: Argentina
facility: Oscar Ronzio
state: Caba
Study officials:
affiliation: Inst. Univer. Fund. H.A. Barceló - U. Maimónides - U. Nac. A. Jauretche
name: Oscar A Ronzio, D.H.Sc
role: STUDY_DIRECTOR
References: