MULTİDİMENSİONAL ASSESSMENT OF MUSCLE FATİGUE İN SOCCER PLAYERS (MAMF)

MULTIDIMENSIONAL ASSESSMENT OF MUSCLE FATIGUE USING ACCELEROMETER, ELECTROMYOGRAPHY AND MUSCLE THICKNESS DATA

Muscle fatigue is a multifactorial physiological phenomenon characterized by a reduction in the ability of a muscle to generate force during sustained or repetitive contractions. This cross-sectional observational study aimed to investigate the relationships among muscle thickness, surface electromyography (sEMG) median frequency, accelerometer-derived mechanical vibration parameters, and isometric force characteristics in healthy male soccer players. Thirty participants aged 18-30 years underwent ultrasonographic muscle thickness assessment, synchronized sEMG and accelerometer recordings, and isometric strength testing at different knee flexion angles (90°, 60°, and 30°). The study evaluated the interaction between morphological, electrical, and mechanical indicators of muscle fatigue to support the development of multidimensional fatigue monitoring approaches.

Study Overview

• Status: Completed
• Conditions: Muscle Fatigue
• Intervention / Treatment: Device: Neuromuscular Assessment Devices

Detailed Description

Muscle fatigue is commonly assessed using surface electromyography (sEMG), particularly through frequency-domain parameters such as median frequency. However, fatigue-related changes are not limited to electrical activity and may also involve alterations in muscle mechanical behavior and morphological characteristics. Accelerometer-derived signals provide information regarding muscle vibrations and mechanical oscillations, while ultrasonographic measurements of muscle thickness provide information about muscle morphology and force-generating capacity.

The purpose of this study was to examine the relationships among muscle thickness, sEMG median frequency, accelerometer-derived mechanical vibration parameters, and isometric force variables during maximal voluntary isometric contractions performed at different knee flexion angles. Healthy male soccer players participated in a laboratory-based assessment protocol including ultrasonography, synchronized sEMG recordings, triaxial accelerometry, and isokinetic dynamometry.

Muscle thickness of the vastus lateralis obliquus (VLO), vastus medialis obliquus (VMO), and rectus femoris obliquus (RFO) muscles was measured using ultrasonography. Participants subsequently performed maximal voluntary isometric contractions at 90°, 60°, and 30° knee flexion angles. Surface electromyography, accelerometer signals, and force-related variables were recorded simultaneously. Median frequency values, acceleration-based root mean square (RMS) parameters, peak torque, mean torque, and time-to-peak torque variables were analyzed.

The study aimed to provide a multidimensional framework for muscle fatigue assessment by integrating morphological, electrical, and mechanical indicators and to explore their associations in healthy athletic populations.

• Study Type: Observational
• Enrollment (Actual): 30

Contacts and Locations

Study Locations

• Turkey (Türkiye)
  • Merkez
    • Ordu, Merkez, Turkey (Türkiye), 52100
      • Ordu University Faculty of Sports Sciences

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult
• Accepts Healthy Volunteers: Yes

• Sampling Method: Non-Probability Sample

Study Population

Healthy male soccer players aged 18 to 30 years who were actively participating in regular football training and competition. Participants were recruited from football teams and underwent assessments of muscle thickness, surface electromyography (sEMG), accelerometer-derived mechanical vibration parameters, and isometric strength during laboratory-based testing sessions. Only individuals meeting all eligibility criteria and providing informed consent were included in the study.

Description

Inclusion Criteria:

• Healthy male soccer players aged 18-30 years
• No lower extremity injury within the previous six months
• No condition limiting lower extremity exercise performance
• No caffeine or stimulant consumption on the testing day
• Non-smoker
• Provided written informed consent

Exclusion Criteria:

• Female athletes
• Serious injury to the dominant leg within the previous year
• Intense exercise within the previous 24 hours
• Use of pain relievers or muscle relaxants on the testing day
• Inability to complete testing procedures

Study Plan

How is the study designed?

Number of groups / cohorts

1

Cohorts and Interventions

Group / Cohort

Intervention / Treatment

Healthy Male Soccer Players; Healthy male soccer players aged 18-30 years who participated in a cross-sectional observational study. Participants underwent ultrasonographic muscle thickness assessment, surface electromyography (sEMG), accelerometer-based mechanical vibration measurements, and isometric strength testing during maximal voluntary isometric contractions performed at different knee flexion angles (30°, 60°, and 90°).

Device: Neuromuscular Assessment Devices; Participants underwent non-invasive neuromuscular assessment procedures using surface electromyography (sEMG), triaxial accelerometers, ultrasonography, and an isokinetic dynamometer. Measurements were performed during maximal voluntary isometric contractions at 30°, 60°, and 90° knee flexion angles. The devices were used exclusively for data collection and assessment purposes. No therapeutic, pharmacological, behavioral, or rehabilitative intervention was administered.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Surface Electromyography (sEMG) Median Frequency	Median frequency (Hz) obtained from the vastus lateralis obliquus (VLO), vastus medialis obliquus (VMO), and rectus femoris obliquus (RFO) muscles during maximal voluntary isometric contractions performed at 30°, 60°, and 90° knee flexion angles.	Day 1

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Muscle Thickness	Ultrasonographic muscle thickness measurements of the VLO, VMO, and RFO muscles (mm).	Day 1
Accelerometer-Derived Mechanical Vibration Parameters	Root mean square (RMS) acceleration values obtained from thigh and shank triaxial accelerometers during isometric contractions.	Day 1
Isometric Strength Parameters	Peak torque, mean torque, and time-to-peak torque measured using an isokinetic dynamometer during maximal voluntary isometric contractions.	Day 1

Collaborators and Investigators

• Sponsor: Giresun University
• Investigators: Principal Investigator: Tuğçe Namazcı, PhD, Giresun Üniversitesi

Publications and helpful links

General Publications

• Karthick PA, Venugopal G, Ramakrishnan S. Analysis of Muscle Fatigue Progression using Cyclostationary Property of Surface Electromyography Signals. J Med Syst. 2016 Jan;40(1):28. doi: 10.1007/s10916-015-0394-0. Epub 2015 Nov 7.

Helpful Links

• Published article related to muscle fatigue assessment using surface electromyography

Study record dates

Study Major Dates

• Study Start (Actual): November 1, 2024
• Primary Completion (Actual): February 20, 2025
• Study Completion (Actual): March 15, 2025

Study Registration Dates

• First Submitted: June 12, 2026
• First Submitted That Met QC Criteria: June 18, 2026
• First Posted (Actual): June 24, 2026

Study Record Updates

• Last Update Posted (Actual): June 24, 2026
• Last Update Submitted That Met QC Criteria: June 18, 2026
• Last Verified: June 1, 2026

More Information

Terms related to this study

• Keywords: Accelerometry; Muscle Fatigue; Surface Electromyography; Muscle Thickness; Mechanomyography
• Other Study ID Numbers: TN-2024-127

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO
• IPD Plan Description: Individual participant data will not be publicly shared. The study was conducted as part of a doctoral thesis, and no formal data-sharing plan has been established. Aggregate study results are reported in publications, while access to underlying data may be considered by the corresponding author on a reasonable request basis and in accordance with applicable ethical and institutional requirements.

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No