FIFA 11+ program; It consists of simple, easily remembered, and time-consuming, sport-specific exercises underlying fair play. Although the FIFA 11+ program is a well-established warm-up protocol for injury prevention among football players, the performance improvement aspect of the program is not often discussed in the literature. The study's objective is to investigate the efficacy of the FIFA 11+ program on sports performance parameters such as dynamic balance, isokinetic muscle strength performance in adolescent amateur male football players.

This study was planned in a randomized controlled experimental type. The footballers of a team from an amateur league will be included in the research. All participants will be tested at baseline and 9 weeks after baseline. The participants will be submitted to the following testing procedures: dynamic balance (Star Excursion Balance Test), muscle strength assessment (Isokinetic assessment). After the baseline measurements will be completed, the control group members will be advised to continue their regular warm-up program. This program consists of jogging and stretching exercises. The experimental group will complete the FIFA 11+ training, which consisted of six different types of running exercises; six exercises with three levels of increasing difficulty to improve the participants' strength, agility, core stability, eccentric control, etc.; and advanced running exercises, such as running across the pitch, bounding, planting, cutting. The FIFA 11+ will be applied to the experimental group 3 times a week for 9 weeks. The control group's warm-up duration will be matched to the experimental group's duration (20-25 min). This routine workout will perform 3 times a week for 9 weeks. At the end of 9 weeks, the evaluations will be repeated (Star Excursion Balance Test, Isokinetic assessment).

Inclusion Criteria:

• ) To accept being a case study member
• ) Being in the 15-18 age range
• ) To be a soccer player in amateur league clubs with experience for at least one year
• ) Having no systemic diseases
• ) Having the necessary mental and physical activity level to be able to take and complete the tests

Exclusion Criteria:

• ) Refusing to be a member of a case study
• ) Having visual impairment and perceptual disorder at a severe level
• ) Having pain that prevents testing
• ) Having diseases with neurological dysfunction
• ) Footballers who stop playing active football during the study period and disrupt the training program by not participating in 3 exercises in a row
• ) Having an injury in the research process
• ) Having an injury in the last six months before the research