Core Endurance and Throw Performance in Young Judokas (JUDO-CORE)

Associations of Core Endurance With Medicine Ball Throw Performance and Static Balance in Young Male Judokas: A Cross-Sectional Study

This cross-sectional study aims to investigate the association between core endurance, medicine ball throw performance, and static balance in young male judokas aged 10-13 years. Core endurance will be assessed using McGill's isometric core endurance protocol, including trunk flexion, trunk extension, and lateral bridge tests. Explosive performance will be evaluated using the backward overhead medicine ball throw test, while static balance will be assessed using the Flamingo Balance Test. Correlation and regression analyses will be conducted to examine the relationships between core endurance and performance variables. The findings may contribute to understanding the role of core endurance in youth judo performance.

Study Overview

• Status: Completed
• Conditions: Balance; Explosive Power; Judo Performance; Core Endurance
• Intervention / Treatment: Other: McGill's Core Endurance Test Battery; Other: Backward Overhead Medicine Ball Throw; Other: Flamenco Balance Test

Detailed Description

Judo is a high-intensity combat sport that requires explosive power, postural control, balance, and efficient force transmission throughout the kinetic chain. Core musculature plays a central role in stabilizing the trunk and transferring force between the lower and upper extremities during sport-specific movements. In judo, throwing techniques such as ippon-seoi-nage, uchi-mata, and harai-goshi require substantial trunk stabilization and rotational force production.

Although previous studies have investigated the importance of core training and trunk muscle function in athletic performance, limited evidence exists regarding the association between core endurance and sport-related performance parameters in young judokas. Understanding these relationships may provide valuable insights for training program design in youth judo athletes.

Therefore, the purpose of this cross-sectional observational study is to examine the association between core endurance, medicine ball throw performance, and static balance in male judokas aged 10-13 years.

Twenty male judokas with at least two years of regular judo training experience will participate in the study. Core endurance will be evaluated using McGill's isometric core endurance test battery, including trunk flexion, trunk extension, right lateral bridge, and left lateral bridge tests. Explosive upper-body performance will be assessed using the backward overhead medicine ball throw test with a 2-kg medicine ball. Static balance performance will be evaluated using the Flamingo Balance Test.

Data collection will be conducted over two testing sessions separated by at least 48 hours. Spearman rank correlation analyses and regression analyses will be used to examine the relationships between variables.

The study hypothesizes that greater core endurance will be positively associated with medicine ball throw performance and static balance performance in young male judokas.

• Study Type: Interventional
• Enrollment (Actual): 20
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Turkey (Türkiye)
  • Malatya
    • Malatya, Malatya, Turkey (Türkiye), 44280
      • epartment of Physical Education and Sport Teaching, Faculty of Sports Sciences, Inonu University,

Participation Criteria

Eligibility Criteria

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

Description

Inclusion Criteria:

• Being a male judoka aged between 10 and 13 years.
• Having at least 2 years of regular judo training experience
• Training at least 3 days per week regularly
• Volunteering to participate in the study and providing parental informed consent
• Being free from any physical injuries or health conditions that could interfere with physical performance testing

Exclusion Criteria:

• Having any acute or chronic musculoskeletal injuries within the last 6 months
• Having a history of surgery that affects physical movement or balance
• Using any medication or supplements that could influence physical performance or balance during the testing period
• Failure to complete all the required test protocols
• Any neurological or vestibular disorders that affect static balance

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm

Intervention / Treatment

Experimental: judokas; A single group of 20 young male judokas (aged 10-13 years) who underwent physical performance testing, including core endurance, medicine ball throw, and static balance assessments.

Other: McGill's Core Endurance Test Battery; Participants performed four isometric endurance tests: trunk flexor, trunk extensor, and right/left lateral bridge tests to assess core stability.; Other: Backward Overhead Medicine Ball Throw; Used to measure explosive power. Participants threw a 2 kg medicine ball backward over their head for maximum distance; Other: Flamenco Balance Test; A static balance test where participants stood on one leg on a metal beam for as long as possible

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Core Endurance (McGill's Test Battery)	Total core endurance measured through four isometric tests: trunk flexion, trunk extension, right lateral bridge, and left lateral bridge. Each test measures the duration (in seconds) the participant can maintain the required position.	Baseline

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Explosive Power (Backward Overhead Medicine Ball Throw)	The maximum distance achieved by throwing a 2 kg medicine ball backward over the head. The best of three trials is recorded.	Baseline
Static Balance (Flamenco Balance Test)	Assessment of static balance where the number of falls or balance losses are counted during a 1-minute period while standing on a metal beam.	Baseline

Collaborators and Investigators

• Sponsor: Inonu University
• Investigators: Principal Investigator: Özgür Eken, PhD, Assoc. Prof, Inonu University

Publications and helpful links

General Publications

• Stockbrugger BA, Haennel RG. Validity and reliability of a medicine ball explosive power test. J Strength Cond Res. 2001 Nov;15(4):431-8.

Study record dates

Study Major Dates

• Study Start (Actual): January 15, 2026
• Primary Completion (Actual): February 15, 2026
• Study Completion (Actual): April 15, 2026

Study Registration Dates

• First Submitted: May 8, 2026
• First Submitted That Met QC Criteria: May 8, 2026
• First Posted (Actual): May 14, 2026

Study Record Updates

• Last Update Posted (Actual): May 14, 2026
• Last Update Submitted That Met QC Criteria: May 8, 2026
• Last Verified: May 1, 2026

More Information

Terms related to this study

• Keywords: balance; cross-sectional study; judo; young athletes; Core endurance; medicine ball throw
• Other Study ID Numbers: INU-JUDO-CORE-2025-01

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO
• IPD Plan Description: The individual participant data will not be shared to maintain the confidentiality of the participants, as per the ethical approval guidelines

Drug and device information, study documents

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