Eccentric and Trunk Stability Exercise Program Effects in Young Soccer Players

Effects of an 8-week Eccentric and Trunk Stability Exercise Program on Muscle Strength and Postural Stability in U19 Elite Soccer Players

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.

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.

Inclusion Criteria:

• 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

Exclusion Criteria:

• 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