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Neural Adaptations to a Single Session of Metronome-Paced Strength Training

Not Applicable
Conditions
Healthy
Interventions
Other: Fractal Paced
Other: Self Paced
Other: Isochronus Paced
Registration Number
NCT06539650
Lead Sponsor
Egas Moniz - Cooperativa de Ensino Superior, CRL
Brief Summary

The aim of the study is to investigate the effects of incorporating variability within a single session of Resistance Training (RT) methods on the neural adaptations along the corticospinal tract and on neuromuscular function. The literature suggests that RTis one of the most common modalities to enhance and restore muscle function and its practice results in adaptation in neural and morphological adaptations. Moreover, it is also known that muscle contraction relies on the coordination and regulation of the descending neural drive from the motor cortex to the motoneurons and from the motoneurons to the muscles. However, traditional RT programs tend not to address this motor control dimension. Recent approaches such as metronome paced strength training have been used to cover this motor control dimension through a greater control and consciousness of movement. However, this methodology tends not to incorporate the inherent variability and complex, fractal-like fluctuations that characterize human movement. The investigators propose that incorporating variability through a fractal-like metronome approach will speed up the neural adaptations which will be useful in injury rehab

Detailed Description

Not available

Recruitment & Eligibility

Status
ENROLLING_BY_INVITATION
Sex
Male
Target Recruitment
30
Inclusion Criteria
  • healthy males
  • aged between 18 and 40 years
Exclusion Criteria
  • Neurologic conditions;
  • Lower limb disabilities or disease;
  • Not able to provide informed consent;
  • Have an implanted device (e.g. pacemakers) or any metal in the body;
  • Medication advised against the application of Transcranial Magnetic Stimulation;
  • History/family history of seizures, brain lesions or head trauma, neurological or psychiatric diseases, epilepsy, migraine

Study & Design

Study Type
INTERVENTIONAL
Study Design
CROSSOVER
Arm && Interventions
GroupInterventionDescription
Fractal PacedFractal PacedStrength training in single leg extension machine, synchronizing each repetition with a fractal-like visual metronome, i.e., a metronome presenting visual external cues with variability within its temporal structure.
Self PacedSelf PacedStrength training in single leg extension machine at participants self pace.
Isochronous PacedIsochronus PacedStrength training in single leg extension machine, synchronizing each repetition with a isochronus visual metronome, i.e., a metronome presenting visual external cues withthe same pace in each repetition (without variability)
Primary Outcome Measures
NameTimeMethod
Corticospinal Silent Period (CSP) changes Pre-to-Post intervention both within and between Fractal paced, Isochronus Paced and Self paced conditionsPRE (before intervention), POST (immediately after the intervention), POST 30 (30 minutes after the intervention), POST 60 (60 minutes after the intervention)

CSP is a parameter extracted through the application of Transcranial Magnetic Stimulation (TMS). This parameter provides information regarding the level of inhibition along the corticospinal tract.

Intracortical Facilitation (ICF) changes Pre-to-Post intervention both within and between Fractal paced, Isochronus Paced and Self paced conditionsPRE (before intervention), POST (immediately after the intervention), POST 30 (30 minutes after the intervention), POST 60 (60 minutes after the intervention)

ICF is a parameter extracted through the application of Transcranial Magnetic Stimulation (TMS). This parameter provides information regarding the level of facilitation within the motor cortex.

Short-Interval Intracortical Inhibition (SICI) changes Pre-to-Post intervention both within and between Fractal paced, Isochronus Paced and Self paced conditionsPRE (before intervention), POST (immediately after the intervention), POST 30 (30 minutes after the intervention), POST 60 (60 minutes after the intervention)

SICI is a parameter extracted through the application of Transcranial Magnetic Stimulation (TMS). This parameter provides information regarding the level of inhibition within the motor cortex.

Lumbar Evoked Potentials (LEP) changes Pre-to-Post intervention both within and between Fractal paced, Isochronus Paced and Self paced conditionsPRE (before intervention), POST (immediately after the intervention), POST 30 (30 minutes after the intervention), POST 60 (60 minutes after the intervention)

LEP is a measure extracted through the aplication of Lumbar stimulation. This measure allow to distinguish the adaptations that occur at spinal level as a result of strength training.

Maximal Compound Action Potentials (Mmax) changes Pre-to-Post intervention both within and between Fractal paced, Isochronus Paced and Self paced conditionsPRE (before intervention), POST (immediately after the intervention), POST 30 (30 minutes after the intervention), POST 60 (60 minutes after the intervention)

Mmax is a measure assessed through peripheral nerve stimulation and represents the maximal capacity of recruit the motoneurons that innerve a muscle

Corticospinal Excitability (CSE) changes Pre-to-Post intervention both within and between Fractal paced, Isochronus Paced and Self paced conditionsPRE (before intervention), POST (immediately after the intervention), POST 30 (30 minutes after the intervention), POST 60 (60 minutes after the intervention)

CSE is a parameter extracted through the application of Transcranial Magnetic Stimulation (TMS). This parameter provides information regarding the level of excitability of the corticospinal tract.

Secondary Outcome Measures
NameTimeMethod
Maximal Voluntary Isometric Contraction (MVIC) changes Pre-to-Post intervention both within and between Fractal paced, Isochronus Paced and Self paced conditionsPRE (before intervention), POST (immediately after the intervention), POST 30 (30 minutes after the intervention), POST 60 (60 minutes after the intervention)

MVIC is defined as the maximal force an individual can produce against an immovable resistance

Coefficient ov variation (CV) changes Pre-to-Post intervention both within and between Fractal paced, Isochronus Paced and Self paced conditionsPRE (before intervention), POST (immediately after the intervention), POST 30 (30 minutes after the intervention), POST 60 (60 minutes after the intervention)

CV is a common linear measure that translates the amount of variability within the signal and is calculated through the standard deviation normalised to the mean of a time series

Sample Entropy (SampEn) changes Pre-to-Post intervention both within and between Fractal paced, Isochronus Paced and Self paced conditionsPRE (before intervention), POST (immediately after the intervention), POST 30 (30 minutes after the intervention), POST 60 (60 minutes after the intervention)

SampEn is a non-linear measure of the temporal structure of force output, being an indicator of the regularity of this physiological output. It is obtained from sustained submaximal isometric contractions and it has been proposed as an indirect index of the capacity of the neuromuscular system to adapt the force output to changes in environment, i.e., its adaptability.

Trial Locations

Locations (1)

Egas Moniz School of Health & Science

🇵🇹

Almada, Monte De Caparica, Portugal

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