## 1 Introduction  
The FIFA 11+ program has emerged as a pivotal intervention in the realm of sports training, particularly for its dual role in enhancing athletic performance and reducing injury risk among athletes [1]. Developed by the International Federation of Association Football (Federation Internationale de Football Association, FIFA), this comprehensive warm-up program is designed to improve neuromuscular control, strength, and balance, which are critical for optimal athletic performance and injury prevention [2,3]. The program has been extensively studied across various sports, demonstrating its effectiveness in reducing injury rates and enhancing performance metrics.  
Agility, vertical jump, and postural balance are interconnected physical capacities that are essential in team sports such as handball. Agility requires rapid changes in direction and speed, and the Illinois Agility Test (IAT) is a widely used measure for assessing this component [4,5]. Structured training programs such as FIFA 11+ have demonstrated improvements in agility in athletes from various sports. For example, [PERSON] et al. [6] and [PERSON] et al. [7] reported significant gains in agility following the implementation of FIFA 11+ in soccer and volleyball players, respectively.  
Similarly, vertical jump performance reflects lower-limb explosive power and is crucial for offensive and defensive actions in handball. The FIFA 11+ program includes pylemetric and strength training components that target this capacity. Prior studies by [PERSON] et al. [8], [PERSON] et al. [9], and [PERSON] et al. [10] reported improvements in vertical jump performance among amateur soccer players, suggesting the program's potential in sports requiring jumping abilities.  
Balance, particularly dynamic postural control, plays a central role in injury prevention and movement efficiency. The Y-Balance Test (YBT) quantifies performance in anterior, posteromedial, and posterolateral directions and provides a composite score that reflects overall dynamic balance [11]. [PERSON] et al. [12] and [PERSON] and [PERSON] [13] have shown that programs incorporating balance training, including FIFA 11+, can significantly enhance balance scores, especially in lower-limb dominant sports.  
Despite the growing body of scholarly literature, research on the application of the FIFA 11+ program in handball remains limited. Of note, the physical demands of handball--characterized by frequent jumping, cutting, landing, and body contact--closely resemble those of soccer and volleyball. This biomechanical similarity justifies the extrapolation of previous findings to the handball context, although sport-specific validation remains necessary.  
Therefore, this study aimed to examine the effects of an 8-week FIFA 11+ training program on agility, vertical jump, and dynamic balance in adult male handball players. It was hypothesized that the FIFA 11+ program would significantly improve performance in:  
1. the Illinois Agility Test (agility),
2. countermovement jump height (lower-limb power), and
3. the Y-Balance Test outcomes, including reach distances in the anterior, posteromedial, and posterolateral directions, as well as the composite balance score (dynamic balance).