MedPath

Effect of Femoral Quadriceps Muscle Length on Fatigue Induced by Neuromuscular Electrical Stimulation

Not Applicable
Not yet recruiting
Conditions
Electrical Stimulation
Interventions
Other: Electrical estimulation
Registration Number
NCT05905406
Lead Sponsor
University of Brasilia
Brief Summary

This study aims To investigate the effects of Quadriceps femoris muscle length on neuromuscular fatigue induced by NMES, muscle performance, discomfort and peripheral oxygen extraction.

Detailed Description

This is a crossover, experimental, randomized and double-blind trial (participant and statistician). The procedures will be performed at the Neuromuscular Performance Laboratory and the Musculotendineal Plasticity Laboratory (LaPlasT) of the Faculty of Ceilândia/University of Brasília to evaluate the neuromuscular fatigue generated during NMES of the QF muscle in different muscle lengths, according to the articular angles of the hip and knee. Participants aged between 18 and 45 years of age, of both sexes, healthy, with body mass index (BMI) between 18.5 and 24.9 kg/ m² (ie eutrophic), who did not perform systematic training to strengthen the lower limbs in the last six months, practitioners or not of recreational sports activities, physically active according to the International Physical Activity Questionnaire (IPAQ), and with minimum torque reach of 20% of MVC during NMES without excessive discomfort. Those who have: edema, dermal injury, limitation of the range of joint motion, deformity or amputation in any part of the lower limbs, as well as a history of patellar dislocation or trauma to the lower limbs or trunk that compromises the results. Also excluded are those with conditions that affect musculotendineal morphology or neuromuscular excitability such as diabetes mellitus type II, familial hypercholesterolemia, neuromuscular disease and severe cardiopathy, or conditions that procedures, such as cognitive impairment, psychiatric disease, chemical dependence or behavioral problems (Dudley-Javoroski et al., 2010). Participants will be initially familiar with assessments and training with EENM. In familiarization, will be performed: Antropometry (height and body mass); location of the motor points; randomization of the order of articular positioning that will be evaluated; muscle enhancement; and three CVIM. The fatigue protocol with NMES will occur at 20% of MVC in positions: bench press with knee at 60º of flexion (Sup60), sitting with knee at 60º (Sen60), bench press at 20º (Sup20) and Sitting with knee at 20º (Sen20). These positions were chosen considering that: (1) SJ60 is the position in which the knee angle provides the optimal QF length for maximum torque production (Scott et al., 2019), and the hip angle provides a neutral length for the RF (Bampouras et al., 2017); (2) QF is commonly stimulated with knees fully extended (Fitzgerald et al., 2003). However, with the knees extended, it is not possible to measure the extensor torque of the knee properly in the isokinetic dynamometer (Babault et al., 2003). Therefore, we chose 20º knee flexion as an approximate position; (3) the hip angle affects the length of RF and myotendinous stiffness of QF (Bampouras et al., 2017), so the knee angles (60º and 20º) will be evaluated with the participants both seated (hip in flexion; 85º) when lying down (hip in extension; 0º). During familiarization, for anthropometric assessment (height, body mass and BMI), participants will be barefoot and wearing light clothes. The BMI will be obtained by the ratio of the weight of the participants in kilos with the square of the height (kg/m2). To determine the level of engagement in physical activities, the IPAQ will be applied, which contains 7 items that assess the frequency (days) and duration (minutes and/ or hours) spent on physical activities in the last week (Scholes et al., 2016). After familiarization, there will be four sessions of fatigue induced by NMES, composed of 20 electrically induced contractions at 20% of CVM (CEI20%). Each session will be as confirmed by the volunteer regarding the absence of any residual muscle discomfort arising from the previous session. The sessions will be initiated with heating and muscle enhancement. The following outcomes will be observed before, during and after the fatigue protocol: CVIM; reflex H, Wave M and voluntary activation level; electromyographic activity; muscular architecture; tendinous properties and tissue oxygen extraction. During the fatigue protocol (five first and five last evoked contractions, will be evaluated: (1) fatigability by the torque decay curve; (2) integral force-time; (3) tissue extraction of oxygen.

Recruitment & Eligibility

Status
NOT_YET_RECRUITING
Sex
All
Target Recruitment
36
Inclusion Criteria
  • Participants between 18 and 45 years of age;
  • Both sexes;
  • Healthy;
  • Body mass index (BMI) between 18.5 and 24.9 kg/ m² (ie eutrophic);
  • Who did not perform systematic training strengthening of the lower limbs in the last six months;
  • Practitioners or not of recreational sports activities;
  • Physically active according to the International Physical Activity Questionnaire (IPAQ);
  • Who with minimum torque reach of 20% of MVC during NMES without excessive discomfort.
Exclusion Criteria
  • Edema;
  • Dermal injury;
  • Limitation of the range of joint motion;
  • Deformity or amputation in any part of the lower limbs, as well as a history of patellar dislocation or trauma to the lower limbs or trunk that compromises the results;
  • Those with conditions that affect musculotendineal morphology or neuromuscular excitability such as diabetes mellitus type II, familial hypercholesterolemia, neuromuscular disease and severe cardiopathy;
  • Conditions that make it impossible to cooperate with procedures, such as cognitive impairment, psychiatric illness, chemical dependence or behavioral problems.

Study & Design

Study Type
INTERVENTIONAL
Study Design
PARALLEL
Arm && Interventions
GroupInterventionDescription
S60Electrical estimulationThe Hip will be positioned at 80°, and knee positioned 60°. The sessions will be initiated with heating and muscle enhancement. The following outcomes will be observed before and after the fatigue protocol: (1) CVIM; (2) voluntary activation level; (3) electromyographic activity; (4) muscular architecture; and (5) tendinous properties. During the fatigue protocol, except for item 1), will be evaluated: (1) fatigue by torque decay curve; (2) integral force-time; (3) muscular architecture; (4) tendinous properties; and tissue oxygen extraction.
S20Electrical estimulationThe Hip will be positioned at 80°, and knee positioned 20°. The sessions will be initiated with heating and muscle enhancement. The following outcomes will be observed before and after the fatigue protocol: (1) CVIM; (2) voluntary activation level; (3) electromyographic activity; (4) muscular architecture; and (5) tendinous properties. During the fatigue protocol, except for item 1), will be evaluated: (1) fatigue by torque decay curve; (2) integral force-time; (3) muscular architecture; (4) tendinous properties; and tissue oxygen extraction.
D60Electrical estimulationThe Hip will be positioned at 0°, and knee positioned 60°. The sessions will be initiated with heating and muscle enhancement. The following outcomes will be observed before and after the fatigue protocol: (1) CVIM; (2) voluntary activation level; (3) electromyographic activity; (4) muscular architecture; and (5) tendinous properties. During the fatigue protocol, except for item 1), will be evaluated: (1) fatigue by torque decay curve; (2) integral force-time; (3) muscular architecture; (4) tendinous properties; and tissue oxygen extraction.
D20Electrical estimulationThe Hip will be positioned at 0°, and knee positioned 20°. The sessions will be initiated with heating and muscle enhancement. The following outcomes will be observed before and after the fatigue protocol: (1) CVIM; (2) voluntary activation level; (3) electromyographic activity; (4) muscular architecture; and (5) tendinous properties. During the fatigue protocol, except for item 1), will be evaluated: (1) fatigue by torque decay curve; (2) integral force-time; (3) muscular architecture; (4) tendinous properties; and tissue oxygen extraction.
Primary Outcome Measures
NameTimeMethod
Fatiguean average of 1 year and half

Fatigue index evoked by electrical stimulation

Secondary Outcome Measures
NameTimeMethod
Muscle stiffnessan average of 1 year and half

Datas from Muscle architecture

Properties of the patellar tendonan average of 1 year and half

cross section area from patellar tendon

Total hemoglobin (total-[Hb/Mb])an average of 1 year and half

tissue extraction

Sensorial discomfort during all phases in protocolan average of 1 year and half

Sensorial discomfort assessed by VAS

Surface electromyographic activity (EMG)an average of 1 year and half

Level of activation of muscle

Deoxidized hemoglobin (deoxy-[Hb/Mb])an average of 1 year and half

tissue extraction

M wavean average of 1 year and half

Analysis of the physiologic variables

Muscle thicknessan average of 1 year and half

Datas from Muscle architecture

Displacement of the tendon-aponeurosis complexan average of 1 year and half

Datas from Muscle architecture

Oxidized hemoglobin (Oxy-[Hb/Mb])an average of 1 year and half

tissue extraction

Reflex Han average of 1 year and half

Analysis of the physiologic variables

Voluntary activation levelan average of 1 year and half

Analysis of the physiologic variables

© Copyright 2025. All Rights Reserved by MedPath