Neural Adaptations to Metronome-Paced Strength Training

NCT06532786 | Recruiting

• 1 other identifier: METROTRAIN - 1403
• Study Type: interventional
• Target: 60
• Locations: 1 country
• Sites: 1

Brief Summary

The aim of the study is to investigate the effects of incorporating variability within 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. It is also known that conditions such as ageing and injury have a negative impact on neural drive to the muscles with consequences at motor control level that are not addressed by traditional RT. 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.

Conditions

Healthy

Keywords

Motor Control; Neuroscience; Neural Adapatations; Transcranial Magnetic Stimulation; Dynamic Systems; Metronome Paced Strength Training

Outcome Measures

Primary Outcomes (7)

• Corticospinal Excitability (CSE) changes across the 4-weeks intervention (PRE to Week1, Week 2, Week 3, POST and follow-up) both within and between Fractal paced, Isochronus Paced and Self paced groups

  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.

  PRE (baseline), W1 (week 1), W2 (week 2), W3 (week 3), POST (week 4), FUP (follow-up 4 weeks after the end of intervention)

• Short-interval Intracortical Inhibition (SICI) changes across the 4-weeks intervention (PRE to Week1, Week 2, Week 3, POST and follow-up) both within and between Fractal paced, Isochronus Paced and Self paced groups

  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.

  PRE (baseline), W1 (week 1), W2 (week 2), W3 (week 3), POST (week 4), FUP (follow-up 4 weeks after the end of intervention)

• Corticospinal Silent Period (CSP) changes across the 4-weeks intervention (PRE to Week1, Week 2, Week 3, POST and follow-up) both within and between Fractal paced, Isochronus Paced and Self paced groups

  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.

  PRE (baseline), W1 (week 1), W2 (week 2), W3 (week 3), POST (week 4), FUP (follow-up 4 weeks after the end of intervention)

• Intracortical Facilitation (ICF) changes across the 4-weeks intervention (PRE to Week1, Week 2, Week 3, POST and follow-up) both within and between Fractal paced, Isochronus Paced and Self paced groups

  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.

  PRE (baseline), W1 (week 1), W2 (week 2), W3 (week 3), POST (week 4), FUP (follow-up 4 weeks after the end of intervention)

• Lumbar Evoked Potentials (LEP) changes across the 4-weeks intervention (PRE to Week1, Week 2, Week 3, POST and follow-up) both within and between Fractal paced, Isochronus Paced and Self paced groups

  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.

  PRE (baseline), W1 (week 1), W2 (week 2), W3 (week 3), POST (week 4), FUP (follow-up 4 weeks after the end of intervention)

• Maximal Compound Action Potentials (Mmax) changes across the 4-weeks intervention (PRE to Week1, Week 2, Week 3, POST and follow-up) both within and between Fractal paced, Isochronus Paced and Self paced groups

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

  PRE (baseline), W1 (week 1), W2 (week 2), W3 (week 3), POST (week 4), FUP (follow-up 4 weeks after the end of intervention)

• StartReact Gain changes across the 4-weeks intervention (PRE to Week1, Week 2, Week 3, POST and follow-up) both within and between Fractal paced, Isochronus Paced and Self paced groups

  StartReact gain is a measure that is calculated following the StartReact protocol. It consists in measuring the participants' reaction times in response to visual stimuli (visual reaction time \[VRT\]), visual stimuli combined with a quiet sound (visual auditory reaction time \[VART\]) and visual startling stimuli (visual startling reaction time \[VSRT\]) and, then, apply the following formula: StartReact gain = (\[VRT - VSRT\]/\[VRT - VART\]).

  PRE (baseline), W1 (week 1), W2 (week 2), W3 (week 3), POST (week 4), FUP (follow-up 4 weeks after the end of intervention)

Secondary Outcomes (6)

• Single leg extension 1RM changes after 4-weeks intervention (PRE to POST and follow-up) both within and between Fractal paced, Isochronus Paced and Self paced groups

  PRE (baseline), POST (week 4), FUP (follow-up 4 weeks after the end of intervention)

• Maximal Voluntary Isometric Contraction (MVIC) changes across the 4-weeks intervention (PRE to Week1, Week 2, Week 3, POST and follow-up) both within and between Fractal paced, Isochronus Paced and Self paced groups

  PRE (baseline), W1 (week 1), W2 (week 2), W3 (week 3), POST (week 4), FUP (follow-up 4 weeks after the end of intervention)

• Sample Entropy (SampEn) changes across the 4-weeks intervention (PRE to Week1, Week 2, Week 3, POST and follow-up) both within and between Fractal paced, Isochronus Paced and Self paced groups

  PRE (baseline), W1 (week 1), W2 (week 2), W3 (week 3), POST (week 4), FUP (follow-up 4 weeks after the end of intervention)

• Coefficient ov variation (CV) changes across the 4-weeks intervention (PRE to Week1, Week 2, Week 3, POST and follow-up) both within and between Fractal paced, Isochronus Paced and Self paced groups

  PRE (baseline), W1 (week 1), W2 (week 2), W3 (week 3), POST (week 4), FUP (follow-up 4 weeks after the end of intervention)

• Motor Unit Action Potentials (MUAP) changes across the 4-weeks intervention (PRE to Week1, Week 2, Week 3, POST and follow-up) both within and between Fractal paced, Isochronus Paced and Self paced groups

  PRE (baseline), W1 (week 1), W2 (week 2), W3 (week 3), POST (week 4), FUP (follow-up 4 weeks after the end of intervention)

Study Arms (3)

Fractal Paced

EXPERIMENTAL

Strength 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.

Other: Fractal Paced

Isochronous Paced

EXPERIMENTAL

Strength 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)

Other: Isochronous Paced

Self Paced

EXPERIMENTAL

Strength training in single leg extension machine at participants self pace.

Other: Self Paced

Interventions

Fractal Paced OTHER

The intervention consists in a metronome-paced strength training session performed 3 times per week (with 48h of rest between sessions), during 4 weeks. Each session consists in 4 sets of 15 repetitions at 65% of the one-repetition maximal (1RM) in single leg extension machine, synchronizing each repetition with fractal external cues presented by a visual metronome. The rest between sets will be set at 2 minutes of rest between sets.

Fractal Paced

Isochronous Paced OTHER

The intervention consists in a metronome-paced strength training session performed 3 times per week (with 48h of rest between sessions), during 4 weeks. Each session consists in 4 sets of 15 repetitions at 65% of the one-repetition maximal (1RM) single in leg extension machine, synchronizing each repetition with isochronus external cues presented by a visual metronome. The rest between sets will be set at 2 minutes of rest between sets.

Isochronous Paced

Self Paced OTHER

The intervention consists in a metronome-paced strength training session performed 3 times per week (with 48h of rest between sessions), during 4 weeks. Each session consists in 4 sets of 15 repetitions at 65% of the one-repetition maximal (1RM) in single leg extension machine, at their own self pace (with no metronome). The rest between sets will be set at 2 minutes of rest between sets.

Self Paced

Eligibility Criteria

• Age: 18 Years - 40 Years
• Sex: male
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)

You may qualify if:

• aged between 18 and 40 years

You may not qualify if:

• 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

Sponsors & Collaborators

• Egas Moniz - Cooperativa de Ensino Superior, CRL: lead
• Fundação para a Ciência e a Tecnologia: collaborator

Study Sites (1)

Egas Moniz School of Health & Science

Almada, Monte de Caparica, 2829-699, Portugal

RECRUITING

Central Study Contacts

João H Oliveira, MSc

CONTACT

913266232; joao.henriques.oliveira@gmail.com

João R Vaz, PhD

CONTACT

967096444; jvaz@egasmoniz.edu.pt

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: SINGLE
• Who Masked: PARTICIPANT
• Purpose: BASIC SCIENCE
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: July 29, 2024
• First Posted: August 1, 2024
• Study Start: September 15, 2024
• Primary Completion (Estimated): August 30, 2026
• Study Completion (Estimated): December 31, 2026
• Last Updated: January 16, 2026

Record last verified: 2026-01

Data Sharing

• IPD Sharing: Will not share

Locations

PT (1)