HOW IS THE GAME EVOLVING?

– Written by Claude Karcher, France and Roger Font Ribas, Spain

Team handball has rapidly evolved into a prominent team sport through significant growth in financial and audience engagement. This evolution emphasizes the importance of understanding game demands to enhance player performance and reduce injuries, requiring that coaches and staff adapt their strategies accordingly.

The physical demands in team sports are shaped by various factors, (e.g., rules, field size, player numbers). This article aims to clarify the evolving demands of elite handball and highlight the factors that mitigate physical challenges for players. Constant elements remain, but significant change has been made in areas (e.g. rules modification, physical attributes). Advances in coaching strategies and technology, such as video analysis and player tracking, have significantly contributed to the sport's development.

Studies have utilized various tracking technologies to monitor external demands in handball. Table 1 outlines these technologies. These systems enhance the accuracy of tracking players' positions and movements indoors, offering precise positioning data and capturing complex movements and sport-specific actions. Despite their detailed performance data, these systems have limitations such as high setup costs, extensive infrastructure needs, and potential portability issues¹. They also face challenges in accurately capturing certain game demands², like the isometric movements of pivots and the complex dynamics of play in confined spaces³. These shortcomings highlight the need for ongoing refinement of tracking technologies to better represent the intricate and dynamic aspects of handball, providing a more comprehensive view of player performance and game demands. Coaches should consider these limitations when using data from these systems, as they may not fully reflect the game's physical and tactical complexities.

Studies in physical demand for handball have reported conflicting results⁴, highlighting the complexity and variability inherent in the sport. To address this issue, we seek to identify factors that influence physical demands in handball, to enhance our understanding of how these demands fluctuate across different settings and conditions.

Indeed, the physical demands in handball are shaped by a wide array of factors that interact in complex ways, leading to a unique set of demands for each game. This variability underscores the importance of a nuanced understanding of the sport's dynamics for coaches and training staff. By acknowledging and adapting to these multifaceted influences, coaches can tailor training regimens, game strategies, and player rotations to optimize team performance and player well-being. Let's highlight the key points that underscore this complexity.

Each playing position in handball comes with specific physical requirements. For instance, wing players need exceptional speed and agility to execute fast breaks and evade defenders, while backs require a blend of power for shooting from a distance and the endurance to participate in both offensive and defensive actions³. Pivots must have the strength for physical play and resilience against defensive pressure. The goalkeeper's role is highly specialized, demanding quick reflexes, agility, and the ability to read the game. Thus, the physical demands vary greatly by position, influencing training focus areas such as endurance, strength, agility, and technical skills³.

The offensive and defensive phases introduce varied physical demands⁵. Offensive play demands quick bursts of speed, agility to navigate through defenses, and the endurance to sustain efforts across multiple attacks. Conversely, defensive play requires players to maintain a high level of physical intensity to counteract offensive maneuvers, necessitating strength for physical confrontations⁶. Similarly, the full-court game, characterized by fast breaks and quick retreats, significantly amplifies these physical demands, increasing the number and the distance of sprints.

Strategic rotation during offensive and defensive phases not only exploits tactical advantages but also manages physical loads effectively³. By rotating players based on their specific strengths—such as utilizing defensive specialists or sharpshooters for offense—teams can dynamically adapt to the game's flow and the opposing strategy. This approach balances physical demands across the squad, optimally leveraging individual skills while mitigating fatigue. Frequent rotation allows teams to maintain a high level of intensity, ensuring players have adequate recovery time, which reduces the risk of overuse injuries and conserves energy for pivotal moments. Total playing time is a critical factor, as prolonged time on the court increases a player's exposure to physical stress, underscoring the need for a well-considered rotation strategy to optimize both performance and health.

Physical demands in handball are not only shaped by the immediate gameplay but also by external factors such as the opposition, location, and the game's stakes^7,8. Facing formidable or aggressive opponents demands more from players physically and tactically, leading to increased fatigue and strategic adjustments⁹. Home advantages have also an impact while familiar settings and supportive crowds can lessen physical strain, whereas away games introduce challenges like travel fatigue and unfamiliarity, amplifying physical demands⁷. Additionally, the heightened intensity and pressure of playoffs or crucial matches may escalate physical demands for players⁹.

Recent modifications to handball rules, including the 2016 goalkeeper rule and the 2022 adjustments to passive play and fast throw-offs, have significantly influenced playing demands. These changes, implemented by the International Handball Federation (IHF), aim to quicken the game's pace, making handball more attractive and dynamic (IHF, IX Rules of the Game, 2022) . The main goals are to shorten the attack phase to encourage more fast breaks and quick attacks, thus increasing game density, action, and consequently, physical demands.

Although the pace of handball games has historically been relatively constant¹⁰, it can significantly vary based on several factors such as ball possession, which is associated with higher running demands in terms of total distance and high-speed efforts, along with more high-intensity actions like jumps, shots, and duels. Scenarios such as temporary 2-minute suspensions or strategic decisions like playing 7 vs. 6 may also affect physical demands¹¹. For instance, situations that require goalkeepers to exit for each ball possession could increase running demands for goalkeepers. Moreover, teams in inferiority often slow down the game pace during suspensions to reduce vulnerability to opponent attacks. Coaches can use norms provided in Table 2 for key variables (e.g. ball possession, fast breaks) to recognize potential fluctuations in physical demands and adapt training accordingly.

The game model also plays a crucial role in shaping game demands, affected by factors like the type of defense (e.g., flat or open, such as 0/6 or 3-2-1), the game's pace (high or low), the frequency of counterattacks, and the use of defensive specialists¹². These factors can lead to varying physical demands; for example, an open defense system might result in more player duels, while a high game pace could require more high-speed running efforts. The defensive system is determined by the coaches' choices, whereas offensive strategies are developed in response to the opponent's tactics. Consequently, coaches can only partly influence playing demands.

After examining the factors that influence game demands, we will review recent research (since 2014) to understand handball's physical performance by measuring the external load (activities and actions executing on the field).

Regardless of the analysis technique, total meters covered is a key variable for understanding the demands on handball players. Initially, studies included all players, but with advancements in technology, data have been refined by specific positions or player lines (1st or 2nd), enabling the design of tailored training tasks. This variable not only reflects the total volume of movement in a match but also informs the metabolic work needed during training. It's crucial to consider both player positions and the game model—despite its frequent neglect—to develop tasks that meet specific needs^3,13. Figure 1 provides an overview of the total distance covered, incorporating various factors from publications since 2014.

Linked to the meters covered in a match, the 'distance per minute' metric provides insights into match intensity by analyzing the distance players cover per minute of play. This measure not only reflects game intensity but also facilitates comparisons with training intensities³. Moreover, normalizing distance by time minimizes the impact of playing time on the total distance covered by the players. Figure 2 presents an overview of meters per minute traveled by players under various conditions, such as playing position and game phase. The variability of these results can be attributed to the factors discussed earlier in this article.

Running at high speeds (HSR, >18 km/h) is a key performance determinant in handball but also increases the risk of muscle injuries, especially in the posterior chain^3,13. Consequently, coaches and trainers must carefully design and adjust training programs to prepare players for these intense demands, now more prevalent in contemporary handball. Although reaching maximum speed during matches is rare due to the limited dimensions of a handball field and team dynamics, HSR remains a crucial measure of game intensity. Scientific consensus (Figure 3) shows that wings, often involved in fast counterattacks, cover the most HSR meters^5,13–15.

It is important to note that within the locomotion demands of handball, field players may execute up to 50% of their movements in non-forward directions, including lateral and backward displacements. This significant amount of multi-directional movement underlines the complexity of physical demands in handball and highlights the need for specialized training that encompasses these diverse movement patterns^12,16.

Handball is characterized by frequent, high intensity actions (e.g. accelerations, decelerations, COD) which significantly influence game demands¹⁷. Accelerations and decelerations, particularly, are crucial for understanding these demands. In the confined spaces of a handball field, players often reach high values in these metrics during 1v1 situations or changes of direction, involving significant braking and speed actions^18,19. Data on these actions are limited, and while there is no consensus on thresholds for analyzing high-intensity actions, studies have shown that players typically perform over 1000 such movements per game, averaging 3.9 ± 1.5 high-intensity events per minute, underscoring their importance for performance^14,18.

Different playing positions exhibit varying levels of high-intensity accelerations (HIA) and decelerations (HID). Wings perform slightly more HIA, with averages of 134.8 ± 60.7, compared to backs and pivots (128.1±55.2 and 112.0±33.6 respectively)¹⁴. Backs and wings display comparable high-intensity deceleration (HID) actions (114.6±51.77 vs. 112.9±56), which are higher when compared to pivots (99.6±28.9)¹⁴. These results are due to wings' critical roles in counter attacks, demanding rapid movements and agility, while backs, responsible for organizing positional attacks, experience “fixation movement” leading to intense eccentric contractions and neuromuscular fatigue¹⁴. Pivots, mainly engaged in static blocking, exhibit fewer dynamic movements, leading to lower HIA and HID.

This play pattern requires specialized training to manage the eccentric loads, particularly for backs, to prevent tissue damage²⁰. The high intensity of game actions emphasizes the need for tailored training to accurately replicate these movements and mitigate injury risks. Strength and conditioning coaches must develop training regimens that enhance muscle and tendon capacity to handle these loads, considering the significant physiological impacts of these contractions²¹.

Technical actions and his derivative are also important to characterize physical demands.  In handball, players must withstand high impacts, provoked by opposing players having to properly prepare their body structures to withstand these uncontrolled perturbations²². Pivots, for example, who register lower levels in many of the external load variables due to the demands of their position, register higher values in this variable (10.6+3:4 vs 8.2±6.3 for backs and 1.8±1.5 for wings) due to the fact that they are constantly in the middle of opposing defenses performing a great deal of strength work, in many cases, isometric¹⁷.

Handball players frequently perform jumping and landing actions, whether for throwing or defensive blocking. Saal et al.¹⁷ reported that backs execute approximately 8.6±6.5 jumps per game, followed by pivots with 6.5±3.6, and wings with 4.6±3.5. Given the frequency of these actions and their association with lower limb injuries—such as injuries to ankles, knees, hamstrings, and hips²²—it is crucial to incorporate varied and high-intensity training for these movements. Training should aim not only to enhance power and height but also to prevent injuries by simulating game-like conditions. Exercises should be designed to train these jumps at maximum intensity, incorporating real disturbances to prepare for the decisive and potentially harmful nature of these actions in matches²³.

Shooting and passing, particularly when performed with maximal intensity, are critical technical actions in handball. Shooting speed is not only a critical factor for success but also a potential source of injuries, with overhead throwing ranking among the most explosive sporting actions (maximal internal rotation velocities up to 7430±1270 deg/sec²⁴. Backs typically exhibit faster shooting speeds compared to other players, often ranging from 24 to over 26 m/s, whereas wings and pivots generally have slower shooting speeds^5,25. Players could also perform different type of throw like overarm shot, underarm shot²⁶, diving shot, wing²⁷, jumping with both feet⁶ that has also specificities.  Passing in elite handball, while generally less intense than shooting, still requires substantial effort that can significantly stress the shoulder, potentially leading to acute or chronic injuries. Backs are the most active, averaging 55.9±51.4 passes per game, significantly more than wings (14.8±10.8) and pivots (23.3±15.1)¹⁷. The stress placed on players' shoulders during shooting and passing significantly depends on the time spent in the offensive phase, their playing position, and skill level with more proficient players typically shooting more frequently.

This underscores the necessity for specialized training designed to address these high demands and mitigate injury risks, especially for backs who are regularly involved in intense shooting actions²⁸. Coaches should train players for diverse throws and passes at high intensity and speed, under defensive pressure, with a focus on the braking mechanics of throwing to lower injury risk²⁹. New technologies such as iBall and shoulder IMUs provide valuable data on shoulder load, shot dynamics, and ball handling, enhancing training and reducing injury risks^25,26,30.

The chaotic game structure significantly impacts play intensity, necessitating player preparedness for the most demanding scenarios to succeed and minimize injuries. Although these worst-case scenarios (WCS) occur infrequently during games, Players must be prepared to withstand the most demanding scenarios to both win games and reduce injury risk³¹. Therefore, it is essential to characterize this effort across different time frames. To date, only few studies has been conducted, with the results detailed in Figure 4. Understanding these results is crucial for designing tasks that effectively replicate these demands.

Apart from the external load, it is crucial to consider its impact on players’ bodies by simultaneously assessing the internal load. This comprehensive approach allows for more effective control of player load³². Reflecting this, Póvoas et al.³³ described handball as an intermittent sport that predominantly utilizes aerobic metabolism, punctuated by high-intensity actions that significantly challenge anaerobic metabolism. This duality underscores the need for tailored training and recovery strategies to address the diverse metabolic demands placed on players³⁴.

Since our last review in 2014, there has been limited new data on internal load measures such as oxygen consumption, heart rate or blood lactate in handball. We recommend that readers consult our previous work for detailed insights. Therefore, there is a clear need for further research in this area, particularly considering the playing position and various game variables³⁵.

Monitoring the physical load in team handball can effectively be done by evaluating hormonal responses during and after exercise, using blood or saliva samples. These responses, particularly the increase in cortisol and decrease in immunoglobulin A observed in studies, indicate significant physiological stress and are valuable indicators of physical loads³⁶. Mariscal et al.³⁷ found that competitive matches in female athletes activate stress pathways, such as the hypothalamic-pituitary-adrenal axis and adrenergic system, leading to decreased immunocompetence. This highlights the need for careful monitoring and management of recovery, as returning to baseline values can take several hours to days.

The miniaturization and the development of diverse sports wearables (e.g. EMG, ECG, NIRS), have the potential to enhance our understanding of the physiological demands of handball³⁸. However, the contact nature of the sport may slightly impede the widespread deployment of these technologies.

As team handball advances, with marked improvements in engagement and technology, grasping its physical demands is critical. This article has examined these demands, shaped by evolving rules, positions, and strategies.

Yet, current technologies fall short of fully capturing the game's physicality, particularly for goalkeepers whose unique role warrants further investigation. As we delve into high-intensity dynamics, the need for ongoing research and training innovation becomes evident to protect player health.

Staff members should apply these findings to devise training programs aligned with competitive demands and player safety. With handball's increasing complexity, coaching and performance analysis must advance accordingly.

Looking ahead, enhanced data collection and insight into the physiological effects of play are essential. This will improve our strategies to elevate performance and reduce injuries, creating a safer, more competitive handball landscape for all players, particularly addressing the underrepresented area of goalkeeper physical demands.

CONCLUSION

Team handball has undergone significant evolution, marked by enhancements in player engagement and technological advancements. This development underscores the need to comprehend the complex physical demands of the sport to optimize player performance and minimize injury risks. The physical requirements in handball are influenced by an array of factors including game rules, player positions, and strategic dynamics, which have been elaborated through the examination of recent rule modifications and the application of advanced tracking technologies.

Despite these advancements, challenges persist in fully capturing the game’s physicality, particularly in the detailed aspects of play and player movements. This gap highlights the need for ongoing refinement of tracking technologies and methodologies to ensure a comprehensive representation of the sport's demands. Such insights are crucial for coaches and training staff as they develop tailored training programs that address both the high demands of competitive play and prioritize player health and safety.

Moreover, the variability in game demands necessitates a nuanced understanding of handball dynamics to effectively adapt training and game strategies. This includes considering the specific physical requirements of different playing positions and the strategic use of player rotations to manage physical loads and prevent injuries. The role of external factors such as opposition strength, game location, and match significance also play a critical part in shaping game dynamics and physical demands.

Furthermore, recent research highlights the need for an enhanced understanding of how physical demands fluctuate, which is crucial for developing interventions that optimize performance and reduce injury risks. However, there remains a notable gap in data, particularly concerning the physical demands on goalkeepers, who often face unique challenges that are not as thoroughly documented as those of outfield players.

In conclusion, as handball continues to evolve in complexity and intensity, so must the approaches to coaching, player development, and performance analysis. This evolution will benefit from more refined data collection methods and deeper insights into the physiological impacts of play, which will collectively enhance our ability to design effective training and recovery protocols. This approach not only promises to foster a safer and more competitive environment but also ensures that all aspects of physical demands, including those less represented like goalkeeper demands, are adequately addressed.

As handball continues to evolve in complexity and intensity, so must the approaches to coaching, player development, and performance analysis. This evolution will benefit from more refined data collection methods and deeper insights into the physiological impacts of play, which will collectively enhance our ability to design effective training and recovery protocols. This approach not only promises to foster a safer and more competitive environment but also ensures that all aspects of physical demands, including those less represented like goalkeeper demands, are adequately addressed.

Claude Karcher PhD

Centre de Ressource, d’Expertise et de Performance Sportive, CREPS de Strasbourg, France

Faculty of Sport Sciences, European Centre for Education, Research and Innovation in Exercise Physiology (CEERIPE), University of Strasbourg,

Roger Font Ribas

Research group in Tecnologia Aplicada a l’Alt Rendiment i la Salut (TAARS)

Tecnocampus, Department of Health Sciences, Pompeu Fabra University, Mataró, Spain

GRCE Research Group, National Institut of Physical Education of Catalonia (INEFC)

Barcelona, Spain.

Contact: claude.karcher@gmail.com

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