Comparison of Trunk Muscle Performance Between Sprinters With and Without Hamstring Strain Injury History

Study Overview
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Brief Summary
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The aim of this study is to: Compare trunk muscle performance between sprinters with and without HSI history Investigate whether running speed influences the differences on trunk muscle activity between these two groups

Detailed Description
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Hamstring strain injury is one of the most common injuries in the lower extremities. As running speed increases, the force and load on the hamstring muscles significantly increase, thereby increasing the risk of injury. Trunk muscles are connected thigh muscles through the pelvis, and poor trunk muscle capacity of maintaining stability affect the muscle length of the lower limbs during movement, reducing their contractile tension and increasing the risk of injury. Earlier literature also indicated that poor trunk muscle performance is related to the occurrence of lower extremity sport injuries. However, literature on the relationship between trunk muscle performance and hamstring strain injury is scarce. Testing methods of existing research have failed to fully reflect the actual circumstances of sprinting. Moreover, previous studies have predominantly focused on soccer players. However, the running mechanics of soccer player and sprinter are slightly different. Currently, there is lack of research investigate the relationship between trunk muscle performance and hamstring strain injury in sprinters.Therefore, the aim of this study is to: (1) Compare trunk muscle performance between sprinters with and without HSI history, (2) nvestigate whether running speed influences the differences on trunk muscle activity between these two groups

Official Title
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Comparison of Trunk Muscle Activity, Muscle Strength, Muscle Endurance Between Sprinters With and Without Hamstring Strain Injury History

Conditions
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Hamstring Injury

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria of HSI history group: Have ≥ twice hamstring strain injury occurrence in the past year Inclusion Criteria of control group: Without any hamstring strain injury occurrence in the past year Match gender, age, BMI, dominant side, training experience, training frequency, Personal best record in 100m with HSI history group Exclusion Criteria of all subjects: Neurological, cardiorespiratory or systemic disorder Have low back pain history in the past year Scoliosis Sacroiliac joint dysfunction Complaints of pain on trunk & lower extremity Leg length difference > 2cm History of lower extremity surgery

Ages Eligible for Study
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Minimum Age: 16 Years
Maximum Age: 30 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 |
| --- | --- |
| Hamstring strain injury history group<br>Sprinters who have ≥ twice hamstring strain injury occurrence in the past year | |
| Control group<br>Sprinters who match gender, age, BMI, dominant side, training experience, training frequency, PB in 100m with HSI history group and without any hamstring strain injury occurrence in the past year | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Surface electromyography (Noraxon TeleMyo sEMG System, Noraxon USA Inc, Scottdale, Ariz) | Muscle activation of external oblique, internal oblique, erect spinae, gluteus maximus when sprinting on the treadmill at 40% and 60% maximal speeds | Immediately during the experiment | 
| Isometric trunk flexor muscle strength (Pro 4, Biodex Medical Systems, Inc., Shirley, NY, United States) | Isometric muscle strength of trunk flexor is measured with Biodex System 4 Pro™ in sitting position | Immediately during the experiment | 
| Isometric trunk extensor muscle strength (Pro 4, Biodex Medical Systems, Inc., Shirley, NY, United States) | Isometric muscle strength of trunk extensor is measured with Biodex System 4 Pro™ in sitting position | Immediately during the experiment | 
| Isometric trunk rotator muscle strength (microFET®2 Digital Handheld Dynamometer) | Isometric muscle strength of trunk rotator is measured with microFET in hook-lying position | Immediately during the experiment | 
| Trunk flexor muscle endurance | Muscle endurance of trunk flexor is measured with trunk muscle endurance test. It requires subjects to sit on the test bench and place the upper body against a support with an angle of 60˚ from the test bed. Both the knees and hips are flexed to 90˚. The arms are folded across the chest with hands placed on the opposite shoulder and toes are placed under toe straps. Subjects will be instructed to maintain the body position while the supporting wedge is pulled back 10cm to begin the test. The test ends when the upper body falls below the 60˚ angle. The time the subjects maintain will be recorded. | Immediately during the experiment | 
| Trunk extensor muscle endurance | Muscle endurance of trunk extensor is measured with Biering-Sorensen test. It requires subjects to lay prone with the lower body fixed to the test bed at the ankles, knees, and hips and the upper body extended in a cantelevered fashion over the edge of the test bench. The test bench surface is approximately 25cm above the surface of the floor. Subjects rest their upper bodies on the floor before the exertion. At the beginning of the exertion the upper limbs are held across the chest with the hands resting on the opposite shoulders, and the upper body is lifted off the floor until the upper torso is horizontal to the floor. Subjects are instructed to maintain the horizontal position as long as possible. The time the subjects maintain will be recorded. | Immediately during the experiment | 
| Trunk lateral flexor muscle endurance | Muscle endurance of trunk lateral flexor is measured with side bridge test. It requires subjects to lay on an exercise mat (thickness, 2.5cm) on their sides with legs extended. The top foot is placed in front of the lower foot on the mat for support. Subjects are instructed to support themselves lifting their hips off the mat to maintain a straight line over their full body length, and support themselves on one elbow and their feet. The uninvolved arm is held across the chest with hand placed on the opposite shoulder. The test ends when the hips returns to the exercise mat. The time the subjects maintain will be recorded. | Immediately during the experiment | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Hamstring Strain Injury, Trunk Muscle Performance, Hip Muscle Performance, Sprinter