Effects of Core and Inspiratory Muscle Training on Muscle Oxygenation and Athletic Performance İn Young Soccer Players

NCT07657065 | Not Yet Recruiting

• 1 other identifier: 2026/78
• Study Type: interventional
• Target: 54
• Locations: 1 country
• Sites: 1

Brief Summary

The purpose of this randomized controlled trial is to investigate the effects of core training and inspiratory muscle training (IMT) on muscle oxygenation and athletic performance in youth male soccer players aged 15-18. A total of 54 healthy soccer players will be included and randomly assigned into three equal groups: the Control Group, the Core Training Group, and the Core Training + IMT Group. All interventions will be implemented for 8 weeks in addition to routine soccer training sessions. Assessments will be performed at baseline (Week 0), mid-intervention (Week 4), and post-intervention (Week 8). The primary outcome measures of the study are aerobic capacity assessed by the Yo-Yo Intermittent Recovery Test Level 1 and muscle oxygenation parameters monitored via near-infrared spectroscopy (NIRS) using a MOXY monitor. Secondary outcome measures include sprint performance, agility, dynamic balance, core muscle strength and endurance, inspiratory muscle strength, lower extremity explosive power, and soccer-specific technical performance tests. Overall, this study aims to reveal the combined effects of core training and inspiratory muscle training on muscle oxygenation, respiratory functions, aerobic capacity, and soccer performance, while explaining the underlying physiological mechanisms in youth athletes.

Conditions

Athletic Performance; Muscle Oxygenation; Respiratory Function

Keywords

Youth Soccer; Core Training; Inspiratory Muscle Training; Near-Infrared Spectroscopy; Aerobic Capacity; Diaphragm

Outcome Measures

Primary Outcomes (3)

• Aerobic Capacity

  Assessed using the Yo-Yo Intermittent Recovery Test Level 1 (Yo-Yo IR1) to determine the total distance covered in meters.

  Baseline (Week 0), Mid-intervention (Week 4), and Post-intervention (Week 8)

• Muscle Oxygen Saturation (SmO2)

  Measured in percentage (%) during exercise using near-infrared spectroscopy (NIRS) via a MOXY monitor to evaluate muscle oxygenation.

  Baseline (Week 0), Mid-intervention (Week 4), and Post-intervention (Week 8)

• Total Hemoglobin (THb)

  Measured in arbitrary units or micro-molar concentrations using a MOXY monitor (NIRS technology) to assess local blood volume changes and muscle hemodynamics.

  Baseline (Week 0), Mid-intervention (Week 4), and Post-intervention (Week 8)

Secondary Outcomes (8)

• 20-Meter Sprint Performance

  Baseline (Week 0), Mid-intervention (Week 4), and Post-intervention (Week 8)

• Agility Performance

  Baseline (Week 0), Mid-intervention (Week 4), and Post-intervention (Week 8)

• Dynamic Balance

  Baseline (Week 0), Mid-intervention (Week 4), and Post-intervention (Week 8)

• Core Muscle Strength and Endurance

  Baseline (Week 0), Mid-intervention (Week 4), and Post-intervention (Week 8)

• Lower Extremity Explosive Power

  Baseline (Week 0), Mid-intervention (Week 4), and Post-intervention (Week 8)

Study Arms (3)

Control Group

NO INTERVENTION

Participants in this group will only continue their routine soccer training program for 8 weeks without any additional core or respiratory intervention.

Core Training Group

EXPERIMENTAL

Participants will perform a structured core training program in addition to their routine soccer training. The intervention will be conducted 3 days a week for 8 weeks, taking approximately 20-25 minutes before soccer practices, using a progressive overload principle.

Behavioral: Core Training Program

Combined Training Group

EXPERIMENTAL

Participants will receive both the structured core training program and inspiratory muscle training (IMT) in addition to routine soccer training. Core training will be done 3 days a week for 20-25 minutes. IMT will be performed 3 days a week using a threshold device (2 sets of 30 breaths), starting at 50% of maximal inspiratory pressure (MIP) and progressing to 70% over 8 weeks.

Behavioral: Core Training Program; Device: Inspiratory Muscle Training (IMT)

Interventions

Core Training Program BEHAVIORAL

A structured, progressive core stability training program targeting trunk and abdominal musculature. The exercises will be conducted 3 days a week for 8 weeks, taking approximately 20-25 minutes before soccer practices.

Combined Training Group; Core Training Group

Inspiratory Muscle Training (IMT) DEVICE

Inspiratory muscle training performed using a threshold device. The protocol consists of 2 sets of 30 breaths per session, 3 days a week for 8 weeks. Training intensity starts at 50% of maximal inspiratory pressure (MIP) and progresses up to 70% MIP.

Combined Training Group

Eligibility Criteria

• Age: 15 Years - 18 Years
• Sex: male
• Healthy Volunteers: Yes
• Age Groups: Child (0-17), Adult (18-64)

You may qualify if:

• Being between 15 and 18 years of age.
• Being a male soccer player.
• Actively and regularly participating in trainings at Alagöz Soccer Club.
• Having participated in regular soccer training for at least the last 6 months.
• Being able to continue routine trainings throughout the study period.
• Being fully informed about the research.
• Having obtained voluntary informed consent, and parental/guardian consent for participants under 18 years of age.
• Having the cognitive and physical capacity to understand and fulfill the specific test and exercise instructions.

You may not qualify if:

• Having a history of lower extremity, trunk-core, or athletic performance-limiting injury within the last 6 months.
• Having undergone orthopedic lower extremity or spine surgery within the last 1 year.
• Having active musculoskeletal pain or any orthopedic/neurological condition that prevents exercise.
• Having any health condition that prevents the safe execution of balance, sprint, agility, jump, or core endurance tests.
• Having asthma, chronic respiratory system diseases, exercise-induced bronchospasm, cardiovascular disease, or a physician-imposed restriction on high-intensity exercise that could affect respiratory muscle or exercise testing.
• Having open wounds, infections, or severe skin sensitivity that prevents the application of sensors placed on the skin.
• Currently participating in another structured respiratory muscle training or structured core exercise program that could affect the study results.
• Having a body mass index (BMI) of 30 kg/m² or above.
• Being deemed unsuitable for the study by the researcher due to safety concerns.
• Withdrawal from the study at the request of the participant or their parent/guardian.
• Missing two consecutive exercise sessions or having an insufficient overall attendance rate.
• Developing an exercise-preventing injury or illness during the study period.
• Occurrence of any safety risk during testing or exercise sessions.
• Non-compliance with the study protocol.
• Starting another additional exercise program during the study.

Sponsors & Collaborators

• Istinye University: lead

Study Sites (1)

Igdir University

Iğdır, 76000, Turkey (Türkiye)

Location

MeSH Terms

Conditions

Respiratory Aspiration

Condition Hierarchy (Ancestors)

Respiration Disorders; Respiratory Tract Diseases; Pathologic Processes; Pathological Conditions, Signs and Symptoms

Study Officials

• Abdurrahim Eyüp CANBALOĞLU, MSc

  IĞDIR UNİVERSİTY

  PRINCIPAL INVESTIGATOR

Central Study Contacts

Abdurrahim Eyüp Canbaloglu, MSc

CONTACT

+90 5346492322; abdurrahim.eyup@gmail.com

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: NONE
• Purpose: BASIC SCIENCE
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Research Assistant & PhD Student

Model Details: This three-arm, parallel-group, randomized controlled trial investigates the isolated and combined effects of core training and inspiratory muscle training (IMT) added to routine training in youth soccer players. Participants will be randomly allocated into three groups: Control Group: Routine soccer training only Core Training Group: Routine training + Core training Combined Group: Routine training + Core training + IMT The intervention will last 8 weeks, with assessments at week 0 (pre-test), week 4 (mid-test), and week 8 (post-test). This design allows for the evaluation of both within-group changes over time and between-group differences. Utilizing multiple measurement time points enables monitoring the dynamic nature of the adaptation process and determining the time-course effects of the interventions.

Study Record Dates

• First Submitted: June 15, 2026
• First Posted: June 18, 2026
• Study Start: August 1, 2026
• Primary Completion (Estimated): August 1, 2027
• Study Completion (Estimated): December 1, 2027
• Last Updated: June 18, 2026

Record last verified: 2026-06

Data Sharing

• IPD Sharing: Will not share

Locations

TU (1)