Lumbopelvic Control in Baseball Batting

Study Overview
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Brief Summary
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Baseball batting is important to winning the games. Baseball batting is achieved by proximal-to-distal sequencing of body movements and controlled by the neuromuscular system. Poor lumbopelvic control could influence production and transfer of energy in the kinetic chain. This study aims to investigate the impact of lumbopelvic control in hitting mechanics and bat swing velocity in high school baseball players.

Official Title
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Influence of Lumbopelvic Control on Batting Mechanics and Bat-swing Velocity in Baseball Players

Conditions
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Athletes

Intervention / Treatment
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* Other: No intervention


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Sport specialization in baseball batting Active players on college baseball teams Exclusion Criteria: History of surgery in the lumbar area Severe musculoskeletal or neurological symptoms that interfere with participation in competition, training and test

Ages Eligible for Study
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Minimum Age: 17 Years

Sexes Eligible for Study
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All

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 |
| --- | --- |
| Stable group<br>Participants display knee valgus less or equal to 15° at 45° knee flexion in the descending phase of the squat on both legs | Other: No intervention<br>* No intervention / Compare the difference in batting mechanics and bat-swing velocity in baseball players with good and poor lumbopelvic control<br>|
| Unstable group<br>Participants display knee valgus greater than 15° at 45° knee flexion in the descending phase of the squat on one leg or both legs | Other: No intervention<br>* No intervention / Compare the difference in batting mechanics and bat-swing velocity in baseball players with good and poor lumbopelvic control<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Ratio of angular displacement of lumbar spine and hip joint | Angular displacement of lumbar spine divided by angular displacement of hip joint | 1 week after enrolled | 
| Bat-swing velocity | Maximal bat swing velocity during baseball batting | 1 week after enrolled | 
| Ratio of angular displacement of thoracic spine and lumbar spine | Angular displacement of thoracic spine divided by angular displacement of lumbar spine | 1 week after enrolled | 
| Timing of maximal angular velocity of hip joint | The time point where the hip joint reaches its maximal angular velocity over the batting phase | 1 week after enrolled | 
| Timing of maximal angular velocity of lumbar joint | The time point where the lumbar joint reaches its maximal angular velocity over the batting phase | 1 week after enrolled | 
| Timing of maximal angular velocity of thoracic joint | The time point where the thoracic joint reaches its maximal angular velocity over the batting phase | 1 week after enrolled | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Batting mechanics, Bat-swing velocity, Lumbopelvic control