Trial Outcomes & Findings for Electrical Stimulation With Different Currents: the Effects on Force, Tolerance and Fatigue in Healthy Subjects (NCT NCT03340337)

Results Overview

Force generated by the patient during a maximal voluntary isometric contraction, measured by an isometric dynamometer with load cell and computer interface. The best of the 3 repetitions was considered. Whenever the third one was the best, additional measurements were taken until a decrease in torque was obtained in order to determine the maximum. Unit: Newtons (N)

Recruitment status

COMPLETED

Study phase

NA

Target enrollment

30 participants

Primary outcome timeframe

MVIC was measured at the beggining of the research, on Day 1. Assessed in an average of 7 min

Results posted on

2021-03-04

Participant Flow

Sampling: Consecutive non-probability. Population: Students pursuing a degree in Kinesiology and Physiatry at Instituto Universitario de Ciencias de la Salud Fundación H.A. Barceló, at Universidad Maimónides and at Universidad Nacional Arturo Jauretche that met the criteria and accepted to participate. Study Start: November 30, 2017 / Study Completion: December 30, 2017

People that did exercise 72 h before the assignment and procedure were not included.

Participant milestones

Participant milestones
Measure	All Participants 1. Measurement of MVIC. 2. All the participants received 3 types of electrical stimulation (Neo-Russian, Aussie and RBS), in a randomized order (balanced permutations, forming 5 x 6 blocks for the three currents). 3. Determination of Maximal Electrical Induced Contraction (MEIC). Dosing information: Contraction parameters: Ramp-up: 1 sec On time: 3 sec Ramp-down: 1 sec Total work time: 5 sec Rest time: 120 sec Reps: 3, whenever the third one was the best, additional measurements will be taken until a decrease in torque will be obtained to determine the maximum. Current parameters: Neo-Russian: Waveform: Rectangular biphasic symmetrical / Carrier frequency: 2500 Hz / Modulation frequency: 50 Hz / Pulse width: 400 us / Duty cycle: 50 %. Aussie: Waveform: Sinousoidal / Carrier frequency: 1000 Hz / Modulation frequency: 50 Hz / Pulse width: 1000 us / Duty cycle: 20 %. RBS: Waveform: Rectangular biphasic symmetrical / Frequency: 50 Hz / Pulse width: 400 us. 4. Washout: 1 week 5. Fatigue test: All the participants received 3 types of electrical stimulation (Neo-Russian, Aussie and RBS), in a randomized order. Dosing information: Contraction parameters: Ramp-up: 1 sec On time: 3 sec Ramp-down: 1 sec Total work time: 5 sec Rest time: 5 sec Reps: 21. Current parameters: Same as previous.
Overall Study STARTED	30
Overall Study Received Neo-Russian	30
Overall Study Received Aussie	30
Overall Study Received RBS	30
Overall Study COMPLETED	30
Overall Study NOT COMPLETED	0

Reasons for withdrawal

Withdrawal data not reported

Baseline Characteristics

Electrical Stimulation With Different Currents: the Effects on Force, Tolerance and Fatigue in Healthy Subjects

Baseline characteristics by cohort

Baseline characteristics by cohort
Measure	All Participants n=30 Participants Maximal Voluntary Isometric Contraction (MVIC) will be measured for data normalization. Then, the subjects will receive 3 types of electrical stimulation (Neo-Russian, Aussie and RBS), in a randomized order. The Maximal Elicited Induced Contraction (MEIC) will be measured. An isometric dynamometer will be used for acquiring MVIC and MEIC. The protocol will be 3 reps x 5 sec work x 120 sec rest and 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. One week later, the subjects will receive a fatigue protocol with the three types of electrical stimulation applied in the randomized order 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.
Age, Continuous	24.6 years STANDARD_DEVIATION 3.06 • n=5 Participants
Sex: Female, Male Female	0 Participants n=5 Participants
Sex: Female, Male Male	30 Participants n=5 Participants
Ethnicity (NIH/OMB) Hispanic or Latino	30 Participants n=5 Participants
Ethnicity (NIH/OMB) Not Hispanic or Latino	0 Participants n=5 Participants
Ethnicity (NIH/OMB) Unknown or Not Reported	0 Participants n=5 Participants
Region of Enrollment Argentina	30 Participants n=5 Participants
BMI	24.71 kg/m^2 STANDARD_DEVIATION 1.99 • n=5 Participants

PRIMARY outcome

Timeframe: MVIC was measured at the beggining of the research, on Day 1. Assessed in an average of 7 min

Population: All the participants received 3 types of electrical stimulation (Neo-Russian, Aussie and RBS), in a randomized order, to determine MEIC and Fatigue. As the MVIC was used to normalize "MEIC" and "Fatigue", all study participants were included into one arm.

Force generated by the patient during a maximal voluntary isometric contraction, measured by an isometric dynamometer with load cell and computer interface. The best of the 3 repetitions was considered. Whenever the third one was the best, additional measurements were taken until a decrease in torque was obtained in order to determine the maximum. Unit: Newtons (N)

Outcome measures

Outcome measures
Measure	All Study Participants. n=30 Participants As the MVIC was used to normalize the data for others outcome measures, all study participants were included into one arm. A short 10-minute walk was taken to warm-up. The patient was positioned in a therapeutic chair with the hip at 110°, stabilizing the trunk (at chest level) and the hip (at the level of the anterior superior iliac spines) with straps. Knee was placed in 90° flexion. A goniometer was used to correctly position the joints at said angles. The patient was instructed to cross his arms over his chest and relax. The subject was blindfolded to prevent him from watching the procedure. The measuring system was attached to the distal end of the right lower limb by means of an ankle brace. The subject was instructed to perform a maximum voluntary isometric contraction. Dosing information: * Knee angle: 90° * Hip angle: 110° * Work time: 3 sec * Rest time: 120 sec * Reps: 3 (Whenever the third one was the best, additional measurements were asked by the software until a decrease in torque was obtained to determine the maximum).	Aussie Electrical Stimulation After measuring the MVIC, subject rested for 120 seconds (while searching for motor points for rectus femoris and vastus medialis). All subjects received all currents in a randomized order. The subject was asked not to make any voluntary contraction. Aussie electrical stimulation was applied. At the higher tolerated intensity, the MEIC was measured and normalized with the MVIC. Dosing information: * Knee angle: 90° * Hip angle: 110° Contraction parameters: Ramp-up: 1 sec On time: 3 sec Ramp-down: 1 sec Total work time: 5 sec Rest time: 120 sec Reps: 3, whenever the third one was the best, additional measurements will be taken until a decrease in torque will be obtained to determine the maximum. Current parameters: Aussie: Waveform: Sinousoidal / Carrier frequency: 1000 Hz / Modulation frequency: 50 Hz / Pulse width: 1000 us / Duty cycle: 20 %. An interval of 120 seconds was also taken between the determinations of the MEIC with each current, in order to minimize fatigue.	RBS Electrical Stimulation After measuring the MVIC, subject rested for 120 seconds (while searching for motor points for rectus femoris and vastus medialis). All subjects received all currents in a randomized order. The subject was asked not to make any voluntary contraction. RBS electrical stimulation was applied. At the higher tolerated intensity, the MEIC was measured and normalized with the MVIC. Dosing information: * Knee angle: 90° * Hip angle: 110° Contraction parameters: Ramp-up: 1 sec On time: 3 sec Ramp-down: 1 sec Total work time: 5 sec Rest time: 120 sec Reps: 3, whenever the third one was the best, additional measurements will be taken until a decrease in torque will be obtained to determine the maximum. Current parameters: RBS: Waveform: Rectangular biphasic symmetrical / Frequency: 50 Hz / Pulse width: 400 us. An interval of 120 seconds was also taken between the determinations of the MEIC with each current, in order to minimize fatigue.
Maximal Voluntary Isometric Contraction (MVIC)	419.68 N Interval 299.51 to 531.77	—	—

PRIMARY outcome

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.

Force generated in the muscle while applying electrical stimulation, measured by an isometric dynamometer with load cell and computer interface. This data (in Newtons) was normalized with the MVIC. Unit: percentage of MVIC

Outcome measures

Outcome measures
Measure	All Study Participants. n=30 Participants As the MVIC was used to normalize the data for others outcome measures, all study participants were included into one arm. A short 10-minute walk was taken to warm-up. The patient was positioned in a therapeutic chair with the hip at 110°, stabilizing the trunk (at chest level) and the hip (at the level of the anterior superior iliac spines) with straps. Knee was placed in 90° flexion. A goniometer was used to correctly position the joints at said angles. The patient was instructed to cross his arms over his chest and relax. The subject was blindfolded to prevent him from watching the procedure. The measuring system was attached to the distal end of the right lower limb by means of an ankle brace. The subject was instructed to perform a maximum voluntary isometric contraction. Dosing information: * Knee angle: 90° * Hip angle: 110° * Work time: 3 sec * Rest time: 120 sec * Reps: 3 (Whenever the third one was the best, additional measurements were asked by the software until a decrease in torque was obtained to determine the maximum).	Aussie Electrical Stimulation n=30 Participants After measuring the MVIC, subject rested for 120 seconds (while searching for motor points for rectus femoris and vastus medialis). All subjects received all currents in a randomized order. The subject was asked not to make any voluntary contraction. Aussie electrical stimulation was applied. At the higher tolerated intensity, the MEIC was measured and normalized with the MVIC. Dosing information: * Knee angle: 90° * Hip angle: 110° Contraction parameters: Ramp-up: 1 sec On time: 3 sec Ramp-down: 1 sec Total work time: 5 sec Rest time: 120 sec Reps: 3, whenever the third one was the best, additional measurements will be taken until a decrease in torque will be obtained to determine the maximum. Current parameters: Aussie: Waveform: Sinousoidal / Carrier frequency: 1000 Hz / Modulation frequency: 50 Hz / Pulse width: 1000 us / Duty cycle: 20 %. An interval of 120 seconds was also taken between the determinations of the MEIC with each current, in order to minimize fatigue.	RBS Electrical Stimulation n=30 Participants After measuring the MVIC, subject rested for 120 seconds (while searching for motor points for rectus femoris and vastus medialis). All subjects received all currents in a randomized order. The subject was asked not to make any voluntary contraction. RBS electrical stimulation was applied. At the higher tolerated intensity, the MEIC was measured and normalized with the MVIC. Dosing information: * Knee angle: 90° * Hip angle: 110° Contraction parameters: Ramp-up: 1 sec On time: 3 sec Ramp-down: 1 sec Total work time: 5 sec Rest time: 120 sec Reps: 3, whenever the third one was the best, additional measurements will be taken until a decrease in torque will be obtained to determine the maximum. Current parameters: RBS: Waveform: Rectangular biphasic symmetrical / Frequency: 50 Hz / Pulse width: 400 us. An interval of 120 seconds was also taken between the determinations of the MEIC with each current, in order to minimize fatigue.
Maximal Electrical Induced Contraction (MEIC)	30.30 percentage of MVIC Interval 12.23 to 53.22	13.44 percentage of MVIC Interval 8.66 to 37.0	10.05 percentage of MVIC Interval 4.86 to 25.25

PRIMARY outcome

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.

Visual Analogue Scale (VAS): Magnitude of pain, marked in a analogue scale by participants, to determine how unpleasant was each type of electrical stimulation (applied in randomized order). Expresed in centimeters. * Minimum value: 0 * Maximum value: 10 * A higher score implicates a worse outcome. VAS was evaluated 3 times, 1 per type of electrical stimulation.

Outcome measures

Outcome measures
Measure	All Study Participants. n=30 Participants As the MVIC was used to normalize the data for others outcome measures, all study participants were included into one arm. A short 10-minute walk was taken to warm-up. The patient was positioned in a therapeutic chair with the hip at 110°, stabilizing the trunk (at chest level) and the hip (at the level of the anterior superior iliac spines) with straps. Knee was placed in 90° flexion. A goniometer was used to correctly position the joints at said angles. The patient was instructed to cross his arms over his chest and relax. The subject was blindfolded to prevent him from watching the procedure. The measuring system was attached to the distal end of the right lower limb by means of an ankle brace. The subject was instructed to perform a maximum voluntary isometric contraction. Dosing information: * Knee angle: 90° * Hip angle: 110° * Work time: 3 sec * Rest time: 120 sec * Reps: 3 (Whenever the third one was the best, additional measurements were asked by the software until a decrease in torque was obtained to determine the maximum).	Aussie Electrical Stimulation n=30 Participants After measuring the MVIC, subject rested for 120 seconds (while searching for motor points for rectus femoris and vastus medialis). All subjects received all currents in a randomized order. The subject was asked not to make any voluntary contraction. Aussie electrical stimulation was applied. At the higher tolerated intensity, the MEIC was measured and normalized with the MVIC. Dosing information: * Knee angle: 90° * Hip angle: 110° Contraction parameters: Ramp-up: 1 sec On time: 3 sec Ramp-down: 1 sec Total work time: 5 sec Rest time: 120 sec Reps: 3, whenever the third one was the best, additional measurements will be taken until a decrease in torque will be obtained to determine the maximum. Current parameters: Aussie: Waveform: Sinousoidal / Carrier frequency: 1000 Hz / Modulation frequency: 50 Hz / Pulse width: 1000 us / Duty cycle: 20 %. An interval of 120 seconds was also taken between the determinations of the MEIC with each current, in order to minimize fatigue.	RBS Electrical Stimulation n=30 Participants After measuring the MVIC, subject rested for 120 seconds (while searching for motor points for rectus femoris and vastus medialis). All subjects received all currents in a randomized order. The subject was asked not to make any voluntary contraction. RBS electrical stimulation was applied. At the higher tolerated intensity, the MEIC was measured and normalized with the MVIC. Dosing information: * Knee angle: 90° * Hip angle: 110° Contraction parameters: Ramp-up: 1 sec On time: 3 sec Ramp-down: 1 sec Total work time: 5 sec Rest time: 120 sec Reps: 3, whenever the third one was the best, additional measurements will be taken until a decrease in torque will be obtained to determine the maximum. Current parameters: RBS: Waveform: Rectangular biphasic symmetrical / Frequency: 50 Hz / Pulse width: 400 us. An interval of 120 seconds was also taken between the determinations of the MEIC with each current, in order to minimize fatigue.
Visual Analogue Scale (VAS)	5.54 score on a scale Standard Deviation 2.26	6.20 score on a scale Standard Deviation 2.57	5.15 score on a scale Standard Deviation 2.59

SECONDARY outcome

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.

Number of repetitions, while applying electrical stimulation, equal to or lower than 50% of the first of 21 reps, previously normalized with MVIC Units: units on scale. Range: from 0 to 21. A higher value represents a worse outcome.

Outcome measures

Outcome measures
Measure	All Study Participants. n=30 Participants As the MVIC was used to normalize the data for others outcome measures, all study participants were included into one arm. A short 10-minute walk was taken to warm-up. The patient was positioned in a therapeutic chair with the hip at 110°, stabilizing the trunk (at chest level) and the hip (at the level of the anterior superior iliac spines) with straps. Knee was placed in 90° flexion. A goniometer was used to correctly position the joints at said angles. The patient was instructed to cross his arms over his chest and relax. The subject was blindfolded to prevent him from watching the procedure. The measuring system was attached to the distal end of the right lower limb by means of an ankle brace. The subject was instructed to perform a maximum voluntary isometric contraction. Dosing information: * Knee angle: 90° * Hip angle: 110° * Work time: 3 sec * Rest time: 120 sec * Reps: 3 (Whenever the third one was the best, additional measurements were asked by the software until a decrease in torque was obtained to determine the maximum).	Aussie Electrical Stimulation n=30 Participants After measuring the MVIC, subject rested for 120 seconds (while searching for motor points for rectus femoris and vastus medialis). All subjects received all currents in a randomized order. The subject was asked not to make any voluntary contraction. Aussie electrical stimulation was applied. At the higher tolerated intensity, the MEIC was measured and normalized with the MVIC. Dosing information: * Knee angle: 90° * Hip angle: 110° Contraction parameters: Ramp-up: 1 sec On time: 3 sec Ramp-down: 1 sec Total work time: 5 sec Rest time: 120 sec Reps: 3, whenever the third one was the best, additional measurements will be taken until a decrease in torque will be obtained to determine the maximum. Current parameters: Aussie: Waveform: Sinousoidal / Carrier frequency: 1000 Hz / Modulation frequency: 50 Hz / Pulse width: 1000 us / Duty cycle: 20 %. An interval of 120 seconds was also taken between the determinations of the MEIC with each current, in order to minimize fatigue.	RBS Electrical Stimulation n=30 Participants After measuring the MVIC, subject rested for 120 seconds (while searching for motor points for rectus femoris and vastus medialis). All subjects received all currents in a randomized order. The subject was asked not to make any voluntary contraction. RBS electrical stimulation was applied. At the higher tolerated intensity, the MEIC was measured and normalized with the MVIC. Dosing information: * Knee angle: 90° * Hip angle: 110° Contraction parameters: Ramp-up: 1 sec On time: 3 sec Ramp-down: 1 sec Total work time: 5 sec Rest time: 120 sec Reps: 3, whenever the third one was the best, additional measurements will be taken until a decrease in torque will be obtained to determine the maximum. Current parameters: RBS: Waveform: Rectangular biphasic symmetrical / Frequency: 50 Hz / Pulse width: 400 us. An interval of 120 seconds was also taken between the determinations of the MEIC with each current, in order to minimize fatigue.
Fatigue	6.5 repetitions Interval 0.0 to 11.5	3.00 repetitions Interval 0.0 to 12.25	0.00 repetitions Interval 0.0 to 0.0

Adverse Events

Neo-Russian Electrical Stimulation

Serious events: 0 serious events

Other events: 0 other events

Deaths: 0 deaths

Aussie Electrical Stimulation

Serious events: 0 serious events

Other events: 0 other events

Deaths: 0 deaths

RBS Electrical Stimulation

Serious events: 0 serious events

Other events: 0 other events

Deaths: 0 deaths

Serious adverse events

Adverse event data not reported

Other adverse events

Adverse event data not reported

Additional Information

Oscar Ronzio

Universidad Maimónides - Universidad Nacional Arturo Jauretche - Instituto Universitario de Ciencias de la Salud Fundación H.A. Barceló

Phone: +54-11-4905-1140

Email: [email protected]

Results disclosure agreements

Principal investigator is a sponsor employee
Publication restrictions are in place