Performance Testing in Young Soccer Players

Study Overview
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Brief Summary
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The aim of this study is to investigate physiological characteristics, body composition and performance indicators among youth soccer players of four age categories (U-12, U-14, U-16, and U-18). Participants will undergo assessment of their body weight, body height and percent of body fat as well as performance testing including flexibility, strength, vertical jump, speed, repeated sprint ability, agility, dribbling and endurance.

Detailed Description
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This study aims at investigating anthropometric, body composition and performance indicators among male youth soccer players. The study will be conducted prior to the preparation period. Initially, participants and their parents (for those under 18 years) will be informed about the benefits, risks and discomforts associated with the study and will provide a written consent. Participants will be instructed to refrain from strenuous exercise for at least 48 hours prior to testing and they will be also asked to consume their normal diet. Prior to testing all participants will be familiarized with testing procedures and specific test. Body weight will be measured on a seca beam balance. Participants' height will be measured by using a fixed stadiometer and the percent body fat will be calculated with bioelectrical impedance analysis. Flexibility will be assessed by using the sit and reach test and the lower body explosive strength will be determined through vertical jump testing (squat jump and counter movement jump without arm swing). Knee flexor and extensor strength will be assessed on an isokinetic dynamometer. Sprint performance will be assessed from a standing start over by infrared photocells with participants running 10m and 30m as fast as they can. The repeated sprint ability will be tested by using linear sprint test including 5 maximum sprints of 30 meters with a 25-second recovery period in-between. Maximal oxygen consumption (VO2max) will be determined by open-circuit spirometry via breath-by-breath analysis during a graded exercise test to exhaustion on a treadmill. Furthermore, participants will be evaluated in agility by using the short dribbling test and the ability to recover after repeated intense exercise through the YO-YO Intermittent Recovery test 1 (only for u-16 and U-18 groups).

Official Title
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Evaluation of Soccer-specific Performance and Body Composition in Youth Soccer Players of Different Age Groups

Conditions
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Physical Performance

Intervention / Treatment
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* Other: Performance testing


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Aged between 11 and 12 years Active soccer players participating in regular soccer practice and competition Training age ≥ 3 years Free of chronic diseases Free of musculoskeletal injury Exclusion Criteria: Musculoskeletal injury Chronic disease Training age ≤ 2 years

Ages Eligible for Study
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Minimum Age: 11 Years
Maximum Age: 18 Years

Sexes Eligible for Study
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Male

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Under-12 (U12) players<br> | Other: Performance testing<br>* Soccer-specific performance will be evaluated by measuring flexibility, jumping ability, maximum speed, repeated spring ability, agility and endurance.<br>|
| Under-14 (U14) players<br> | Other: Performance testing<br>* Soccer-specific performance will be evaluated by measuring flexibility, jumping ability, maximum speed, repeated spring ability, agility and endurance.<br>|
| Under-16 (U16) players<br> | Other: Performance testing<br>* Soccer-specific performance will be evaluated by measuring flexibility, jumping ability, maximum speed, repeated spring ability, agility and endurance.<br>|
| Under-18 (U18) players<br> | Other: Performance testing<br>* Soccer-specific performance will be evaluated by measuring flexibility, jumping ability, maximum speed, repeated spring ability, agility and endurance.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Flexibility | Flexibility will be assessed by using the sit-and-reach test | At baseline | 
| Jumping ability | Jumping ability will be assessed by measuring the vertical jumping performance using two different techniques: i) countermovement and ii) squat jump. | At baseline | 
| Maximum speed | Maximum speed will be assessed over 10 m and 30 m by using light cells | At baseline | 
| Repeated sprint ability | Repeated sprint ability will be assessed by performing five 30-m sprints with 25 seconds recovery period in-between, and using light cells. | At baseline | 
| Agility | The ability to change direction while dribbling the ball (termed agility) will be assessed by using the short dribbling test (performed according to standard procedures). | At baseline | 
| Endurance | Endurance will be assessed by using the Yo-Yo Intermittent Recovery test level 1 | At baseline | 
| Maximal oxygen consumption (VO2max) | Maximal oxygen consumption will be measured by open-circuit spirometry via breath-by-breath analysis during a graded exercise test to exhaustion on a treadmill, using automated pulmonary gas exchange system. | At baseline | 
| Knee flexor and extensor strength | Concentric and eccentric peak torque of knee flexors and extensors in both limbs (dominant and non-dominant) will be assessed on an isokinetic dynamometer | At baseline | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Body height | Body height will be measured on a beam balance with stadiometer. | At baseline | 
| Body weight | Body weight will be measured on a beam balance with stadiometer. | At baseline | 
| Body composition | Body fat and fat-free mass will be estimated by using bioelectrical impedance. | At baseline | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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soccer, performance, youth