Eccentric and Trunk Stability Exercise Program Effects in Young Soccer Players
- Conditions
- Muscle StrengthPostural Balance
- Interventions
- Other: Sliding leg curlOther: Balance trainingOther: Core stability
- Registration Number
- NCT04329273
- Lead Sponsor
- Konstantinos Dafkou
- Brief Summary
The purpose of the present study is to investigate the effects of an in-season mixed training program on several physiological parameters of soccer players. Twenty-one U19 elite soccer players recruited and randomly assigned to either an 8-week specific training experimental group or a control group. The program will include an eccentric hamstring exercise, static balance exercises and core muscles strengthening exercises. Isokinetic hamstring and quadriceps strength, single leg static balance and lumbopelvic stability will be measured prior and after the intervention.
- Detailed Description
A total of 123 male Under-19 (U19) players from several soccer teams were initially invited for participation in the study after signing informed consent forms. following a second contact with the participants, questionnaire forms with inclusion and exclusion criteria were send for completion.
Based on their self-report and a clinical examination by a health professional, of the 103 players, 42 did not meet the inclusion criteria, while 12 players did not participate for personal reasons. Of the remaining 69 players, 48 players were excluded, including 3 players reporting an anterior cruciate ligament reconstruction, 14 because of lower extremity injury led to more than two weeks absence from training and 10 players because of secondary injuries or health problems that led to loss of training the past 3 months.
A neutral, blinded investigator with no further involvement in the study was responsible for randomized allocation of participants in two groups. All training sessions in the training group will be supervised by a fitness coach, who will ensure that the exercises are performed according to protocol.
Recruitment & Eligibility
- Status
- COMPLETED
- Sex
- Male
- Target Recruitment
- 21
- 16 to 19 years old soccer players
- Trained at least 3 times and played 1 match weekly, the past 4 years
- Healthy
- Free from muscle injuries in the 6 months prior to the study
- History of anterior cruciate ligament rupture
- History of ankle, hip or knee injury with duration at least 1 week, in the 3 months prior to the study
- Muscle injury with duration at least 1 week, in the 3 months prior to the study
- Any reason resulting in 2 weeks loss of training the preceding 6 months
- Involvement in hamstring strengthening, core stability or balance training program in the 6 months prior to the study
Study & Design
- Study Type
- INTERVENTIONAL
- Study Design
- PARALLEL
- Arm && Interventions
Group Intervention Description Training group Core stability For the balance exercise the participants will perform one-legged stance of certain duration, on a stable surface. For the sliding leg curl exercise the participants lay supine on a mat, wearing only socks in order to create a slippery surface between their heels and the gym floor. The player begins by extending the hip and having the working leg on knee flexion. The contralateral limb is on hip flexion and knee flexion. The base of support is the shoulder blades, the elbows and the heel of the working leg. After assuming this position, the player begins to extend the knee, as slowly as possible, resisting the low friction properties of the ground. The core stability program consists of front plank, side planks, supine bridge, leg lowering and superman exercise. These exercises will be performed at the end of the training session, in contrast to the balance and hamstring exercises which will be executed before the training session. Training group Sliding leg curl For the balance exercise the participants will perform one-legged stance of certain duration, on a stable surface. For the sliding leg curl exercise the participants lay supine on a mat, wearing only socks in order to create a slippery surface between their heels and the gym floor. The player begins by extending the hip and having the working leg on knee flexion. The contralateral limb is on hip flexion and knee flexion. The base of support is the shoulder blades, the elbows and the heel of the working leg. After assuming this position, the player begins to extend the knee, as slowly as possible, resisting the low friction properties of the ground. The core stability program consists of front plank, side planks, supine bridge, leg lowering and superman exercise. These exercises will be performed at the end of the training session, in contrast to the balance and hamstring exercises which will be executed before the training session. Training group Balance training For the balance exercise the participants will perform one-legged stance of certain duration, on a stable surface. For the sliding leg curl exercise the participants lay supine on a mat, wearing only socks in order to create a slippery surface between their heels and the gym floor. The player begins by extending the hip and having the working leg on knee flexion. The contralateral limb is on hip flexion and knee flexion. The base of support is the shoulder blades, the elbows and the heel of the working leg. After assuming this position, the player begins to extend the knee, as slowly as possible, resisting the low friction properties of the ground. The core stability program consists of front plank, side planks, supine bridge, leg lowering and superman exercise. These exercises will be performed at the end of the training session, in contrast to the balance and hamstring exercises which will be executed before the training session.
- Primary Outcome Measures
Name Time Method Peak concentric and eccentric torque of hamstrings and quadriceps Change from baseline assessment at 8 weeks Peak torque (N.m) is measured using isokinetic dynamometer at each angular velocity (30°·s-1, 180°·s-1, 240°·s-1).
Total sway of the center of pressure (CoP) Change from baseline assessment at 8 weeks This is defined as the average distance (mm) of the CoP from the reference lines and the amplitude is its standard deviation
- Secondary Outcome Measures
Name Time Method Average speed of CoP Change from baseline assessment at 8 weeks This reflects the amplitude and frequency of CoP movements and is calculated as the total length of the path of CoP divided by the test trial time (mm·s-1 )
Conventional hamstrings to quadriceps ratio Change from baseline assessment at 8 weeks This is calculated by dividing peak isokinetic concentric hamstring strength by the peak isokinetic concentric quadriceps strength, at the same angular velocity
Angle at peak torque of hamstrings and quadriceps Change from baseline assessment at 8 weeks The angle at which peak torque of hamstrings and quadriceps muscles was achieved, at each angular velocity, measured in degrees (°)
Mixed hamstrings to quadriceps ratio Change from baseline assessment at 8 weeks This is calculated by dividing peak isokinetic eccentric hamstring strength at 30°·s-1 by the peak isokinetic concentric quadriceps strength at 240°·s-1
Dynamic hamstrings to quadriceps ratio Change from baseline assessment at 8 weeks This is calculated by dividing peak isokinetic eccentric hamstring strength by the peak isokinetic concentric quadriceps strength, at the same angular velocity
Trial Locations
- Locations (1)
Laboratory of Neuromechanics, Department of physical education and sport sciences, Aristotle University of Thessaloniki
🇬🇷Serres, Greece