An intrinsic case study design was applied to capture in-depth information on the development process of a world-class female team handball player. A pragmatic realist approach was adopted, which acknowledges the existence of an objective reality recognizing that our understanding of this reality is shaped by context and the perspectives of those involved. Specifically for this study, we were seeking a comprehensive and balanced exploration of the athlete's developmental path by integrating both objective (e.g., training data, performance statistics) and subjective (interviews) perspectives. Ontologically, we acknowledge the existence of a reality that can be studied; however, we emphasize that its understanding is inherently shaped by the context in which it occurs and by the perspectives of those involved. This means that while phenomena may exist independently, their meaning and interpretation are constructed through social and experiential lenses. Epistemologically, we align with a relational perspective, where knowledge is co-constructed through the interaction between the researcher and participants. Rather than being discovered in isolation, insights emerge through dialogue, reflection, and shared meaning-making within the research process. This permits us to capture both objective historical training data and subjective interpretations to provide a comprehensive understanding of the athlete's development within real-world contexts. The present study design and approach has been applied in several recent studies of best practice training and performance development (31–33).

The primary case subject is a Norwegian female world-class handball player (age 34 y, height 168 cm, and body mass 62 kg at the time of data collection) whose developmental trajectory from childhood to elite performance provides a unique opportunity to explore the interplay between long-term training, environmental influences, and physiological and psychological factors. She started with organized handball practice at the age of 7 and played for a local and age-specific team for nine seasons, followed by six handball seasons for two Norwegian upper league clubs (16–22 y), four seasons for a French league club (22–26 y) and finally seven seasons for a Hungarian league club (26–33 y). Furthermore, she played for the youth national team (15–17 y), the junior national team (17–19 y) and finally the senior national team (19–33 y), where she was the team captain for the last nine seasons. She also attended a high school with a sport program when she was 16–19 y.

The player's team handball merits include three Olympic medals (one gold, two bronze), five World Championship medals (three gold, two silver), six European Championship medals (five gold, one silver), three Champions League titles, four national upper league championship titles, three domestic (main) cup titles, one gold from Junior World Championship, and one gold from Junior European Championship. Individual awards include International Handball Federation's (IHF) World Player of the Year (2019), All-Star Centre Back of the Summer Olympics (2024), Most Valuable Player (MVP) in World Championship (2017), All-Star Centre Back of the World Championship (2015, 2023), All-Star Centre Back of the European Championship (2018, 2020, 2022), All-Star Centre Back of the Champions League (2019, 2020, 2021, 2022), MVP in Champions League Final4 (2024), MVP in the French Championship (2014), French Championship Best Playmaker (2014, 2016), All-Star Centre Back of the Norwegian Upper League (2011), and All-Star Centre Back of the Junior World Championship (2010).

The data collection involved five key informants: 1.

The case subject (from now on referred to as “the player”) was the primary informant, providing training data and personal insights into her experiences, perspectives, and internal processes across age stages/seasons and clubs/teams.

The data collection for this study took place between October 2024 and June 2025. A pragmatic three-step procedure was used to collect and refine comprehensive information on the development process of the player: 1.

Historical training data, including training records, plans, and developmental logs from the ages of 7–33 were gathered from personal archives and documented by the informants. For the purpose of this study, the training was classified as recorded time in either handball-specific training, physical conditioning or other sport activities. The physical conditioning was in turn categorized as strength/power (in the gym) or endurance training. Reported test results for the case subject were assessed at the Norwegian Olympic Training Centre according to previously described procedures for throwing velocity (34, 35), sprint (36, 37), countermovement jump (38), Keiser leg press (39), bench press (34) and beep test (40). The player's match activities and statistics from the age 16 were retrieved from publicly available websites of the Norwegian, French, Hungarian and European Handball Federation (41–45). To ensure consistent year-by-year comparisons in terms of training and games, season start and end were set to July 1st and June 30th, respectively.

Numerical information (i.e., background information and physical test scores) was systematized in Microsoft Excel (Microsoft Corporation, Redmond, WA, USA). Typical in-season training plans for two consecutive weeks across the player's three upper-league clubs emerged from a combination of typical range in annual training time and number of sessions, time distribution across different training forms and exercise modalities and intensity zones, the amount and type of intensive sessions, as well as typical weekly training volume, training within intensity zones and exercise modalities for typical in-season training weeks across three different time points and contexts (17, 23 and 32 years; Norwegian, French, and Hungarian clubs, respectively). Preliminary summaries of typical training weeks were cross-referenced with historically reported training logs provided by the athlete and further refined through a systematic revision and negotiation process with all informants.

For qualitative information on (a) the practice of training, (b) key athlete characteristics and (c) environmental factors, a systematic six-step procedure inspired by reflexive thematic analysis as proposed by Braun and Clarke (46) was used to analyze the interview transcripts. Step one involved familiarization with the material and initial discussions among all authors. Then, raw themes were identified by level 1 and level 2 coding procedures (step 2) and organized into five, five and three main themes for key training features, athlete characteristics and environmental factors, respectively (step 3). The revision of themes was the result of discussions among authors and a comprehensive structured negotiation process between researchers and participants to assure accuracy and resonance of interpretations (step 4). In the final definition of themes (step 5), contextualization with previous literature on training science was addressed. Ultimately, all authors collectively contributed to writing of the final manuscript, and all presented results were confirmed and approved by all informants (step 6).

The present study shows that large training volumes were undertaken by the investigated player to reach world-class level in handball. The ∼600 annual training hours from age 16 onwards are comparable to those reported for world-class soccer players and middle-distance runners (47, 48), but considerably lower than previously reported volumes for endurance athletes and a world-leading tennis player (31, 32, 49). However, comparisons across sports have limited relevance, as quantification methods and operationalization of measurable indicators may vary considerably. Moreover, exercise modality significantly affects training load management (50). Handball is characterized by a combination of weight-bearing exercise, physical duels and lower-limb plyometric actions (2–6, 8), which result in high impact forces and, consequently, lower feasible training volumes compared to other, more “gentle” sports. An annual volume of 300–350 h of handball-specific training appeared to represent the player's upper threshold, a plateau reached already in her mid-teens (Figure 1). However, it is important to distinguish training volume from training load in this context, as the performance standard of the teammates and opponents affects the training load considerably. The higher the performance standard, the faster and more intensive play, placing greater demands on the neuromuscular system. Given that the player's volume of specific training remained relatively constant across four different upper-league clubs and three prominent European leagues, it may be speculated if 300–350 h·y⁻¹ represents a general upper limit in female top-level handball.

Determining appropriate sport-specific training loads involves careful consideration. On one hand, a substantial volume is necessary to refine technical-tactical skills and develop the requisite physical attributes. On the other hand, high training loads at an early age may increase the risk of overuse injuries, reduce enjoyment, elevate psychological strain, and potentially lead to dropout from sport (21–28). Notably, the absence of unorganized training during childhood and adolescence observed in this study may represent a potential area for further enhancing the overall performance level in handball. While the present player accumulated 5,000 h of total training by 20.8 years of age, previous studies of soccer players have reported reaching similar volumes between ages 14 and 16, with unorganized training comprising the largest portion of total training volume during childhood and youth (51–54). The differences become substantially more pronounced if only specific training is considered (Figure 2). However, the limited availability of handball courts, particularly during the winter months, likely represents a structural constraint. Relevant authorities should therefore consider implementing initiatives to address these infrastructural challenges.

Seemingly, the diversified training undertaken during childhood and youth laid a solid foundation for the player's subsequent career. Although talent development research has revealed considerable variation both within and across sports regarding pathways to elite performance, there is a general and growing trend supporting versatile training and late specialization during childhood. Overall, the present athlete followed a hybrid approach observed in other elite performers, meaning early engagement in the specific sport combined with cross-sport sampling over a relatively extended period (31, 47). However, this does not necessarily imply that participation in other sports at a young age is essential or that it directly enhances the level of expertise ultimately achieved in handball. Regardless of whether an athlete follows a diversified or early specialization pathway, their sport-specific and personal development, as well as their health and well-being, should remain central to any talent development process (55). For optimal developmental outcomes in young athletes, success should be defined in terms of effort, skill improvement, and the cultivation of positive interpersonal relationships, rather than purely in terms of winning (56). Indeed, the present player's handball training with local, age-specific teams during childhood and adolescence was strongly guided by these principles.

Another key success factor in the player's development was the early introduction and consistent implementation of physical conditioning (strength training in particular) throughout the seasons. This training was instrumental in her development into a world-class player, and her distinctive physique became a clear asset on the court. Indeed, the presented test results (Table 2) appear impressive when compared to available data on elite female handball players (10–16, 36–39). Moreover, the player's injury rate during her entire career was very low compared to what previous studies have reported for female elite handball players (17–20). Whether this low injury rate can be attributed to physical conditioning, favorable genetics, or simply luck remains speculative, as many of the player's teammates followed similar conditioning regimes and still experienced severe injuries. Indeed, sports injuries cannot be attributed to a single factor, as their nature is multifactorial (57).

During the teens, the player was selected for several developmental activities initiated by regional and national levels of the Norwegian Handball Federation. Previous studies of other sports have questioned such initiatives, as success at the adolescent or junior level is a poor predictor for long-term success at the senior level (24). However, Bjørndal et al. (58) reported that having youth and junior international experience was strongly associated with the number of matches played at the senior international level in handball. According to several informants in this study, most Norwegian female senior national team players over the past decade have also represented the junior national team, although exceptions do exist. Overall, the above-mentioned initiatives allowed the player to build a personal framework for evaluating and guiding her own athletic development. The comprehensive, regional-level approach to talent cultivation also served as a socializing mechanism, familiarizing her with the expectations and practices associated with elite performance preparation. Consistent with previous findings on talented handball players (59), pushing oneself to the edge of one's capabilities was seen as essential for advancement. Like the present player, these individuals greatly valued the chance to train alongside peers who matched or exceeded their skill level.

The large increase in the player's training volume from age 15–16 (Figure 1) represents a clear violation of one of the most fundamental principles in training science, namely the principle of progression. While she navigated this period without sustaining severe injuries, other handball players typically experience an increase in overuse and injury-related problems at this career stage (59, 60), thereby counteracting long-term development processes. However, the coaches in this case prioritized the player's health over the team's performance needs. It should be noted that the above-mentioned increase in training volume was primarily due to greater doses of physical conditioning, which possibly served as a kind of “vaccine” against potential handball-related injuries. Moreover, although the academic demands were well coordinated with the sporting schedules, the player still experienced the combined pressures as stressful at times, consistent with previous findings on handball players facing similar dual-career challenges (58). Gifted athletes often acknowledge the challenge of balancing a vibrant social life with the demands of a competitive sports career, where education, training, competition, and social life frequently become intertwined (59).

Generally, when several actors are involved simultaneously, the complexity of training activities and competitions increases. According to Bjørndal et al. (58), a talented Norwegian 17-year-old player may regularly relate to more than ten different coaches in various arenas, such as club teams, schools, regional activities or youth/junior national teams. Interacting with multiple coaches across different team environments, each with their own perspectives on athlete development, can lead to conflicting guidance. Many promising handball players have reported experiencing tension due to differing opinions among coaches regarding how to best prioritize and tailor their training routines (58). A high level of communication, cooperation, and coordination among the involved coaches is therefore essential to ensure purposeful and holistic development (61), and this was clearly evident in the case of the present player. The fact that some of her coaches were employed both at the club and the high school was likely beneficial in this regard. While evidence in the literature also suggests that coach turnover or replacement can affect players' injury rate, along with the sheer number of individuals influencing an athlete's training program (61–63), the present player managed to maintain consistency, quality, and strategic alignment of her development process.

Overall, the present player can be considered a successful product of the Norwegian heterarchical talent development model. The starting point was club-based practice and competition, driven by her mother and other parents. As the player advanced through adolescence, she transitioned to higher-level teams and took part in developmental activities initiated by sport schools and the regional and national levels of the Norwegian Handball Federation. Her successful pathway was also marked by exposure to adult-level practice and competition during adolescence. Training alongside and receiving guidance from more experienced athletes appears to provide meaningful developmental advantages for younger athletes. Such interactions can foster the acquisition of technical skills, promote effective training habits, and provide valuable insights into managing adversity and navigating key transition phases (64, 65). Talent development environments that actively promote cross-age training, such as integrating youth athletes into senior-level sessions, can help demystify the demands of higher performance levels and ease the transition toward elite sport (66, 67).

Because no actors in Norwegian handball are fully in charge of the holistic talent development process or possess superior instructional authority (30), each player is left with considerable responsibility for their own development. In the present study, several core personality traits emerged as critical to the player's successful development, and these attributes align closely with existing literature on the psychological characteristics of elite athletes. According to several talent development studies, successful athletes possess high levels of motivation, dedication, confidence, mental toughness, and a strong sense of ownership of the training process (22, 25), traits that align well with those of the present player. Moreover, a development-oriented mindset is a common attribute among elite performers (68). Athletes with this mindset tend to embrace challenges and view effort as essential to mastery. Several times, the present player voluntarily transitioned to higher-level clubs with the intention of enhancing the performance development. Moreover, although the present player had physical limitations in terms of short stature, she compensated by developing exceptional skills in speed, feints, and change-of-direction capabilities to outperform her opponents. Within this setting, talent development in sport is to an increasing extent driven by an asset-based understanding where athlete empowerment represents a key feature (55). Fostering athlete empowerment contributes to an increased sense of autonomy and responsibility in the development process. When individuals are encouraged to set personal goals, evaluate their performance, and actively engage in improvement strategies, it often leads to enhanced self-regulation and a more disciplined approach to training. This sense of ownership, as also observed in the present case, is frequently linked to stronger intrinsic motivation and sustained effort over time (55).

The player's ability to manage the inevitable challenges encountered on the road to elite performance also reflects a psychological characteristic commonly seen in top-level athletes. Rather than being discouraged by adversity, they often use such experiences as opportunities for reflection and growth, enabling them to redefine their goals and support continued development (68, 69). Collins and MacNamara (69) suggest that experiencing a certain level of challenge and adversity is not merely beneficial but fundamental to achieving elite performance. They argue that exposure to such difficulties is an essential part of talent development, highlighting the importance of deliberately incorporating appropriately scaled challenges into the developmental process.

The empathetic nature of the present player is particularly noteworthy, as this trait is less commonly emphasized in traditional performance-focused models but may play a crucial role in team sports such as handball. Empathy contributes to emotional intelligence, which has been shown to enhance communication, cohesion, and leadership within teams (70). It may also support athletes' ability to respond constructively to feedback and foster positive relationships with coaches and teammates. Taken together, the psychological characteristics observed in the present player resonate strongly with prior research identifying key non-cognitive traits that underpin elite sport development. Moreover, the combination of high task orientation (discipline, dedication) with prosocial traits (empathy) and adaptability (resilience, growth mindset) may offer a particularly robust psychological profile conducive to both individual excellence and effective team integration.

Several environmental factors also contributed to the exceptional performance development, and the mother was the most important single person behind the athlete's success. Parents who consistently offer emotional support through encouragement, praise, and understanding play a pivotal role in nurturing athletes' self-efficacy, intrinsic motivation, and resilience (71). Young talents often view their parents as role models, particularly when parents demonstrate hard work and persistence. In the present case, the player developed an interest in handball after observing her mother during team practices and games. Research emphasizes that a moderate level of positive parental involvement, supportive but not overbearing, is most beneficial (72). Over-instruction or excessive pressure can diminish intrinsic motivation and disrupt the athlete–coach relationship. In contrast, supportive behaviors such as non-directive encouragement strengthen motivation and enjoyment, both of which are essential for long-term engagement and performance (72). Overall, strong family support constitutes a cornerstone in the developmental years of sporting talents (25). Most athletes depend on their parents to help them manage daily responsibilities, including transportation and food preparation, and families are often highly involved in all aspects of their children's handball careers (59). This was also the case for the present player.

The investigated player was consistently under the guidance of skilled and acknowledged coaches. She expressed that all her coaches believed in her potential and were willing to invest in her development, which made her feel safe and welcomed. It remains unknown whether this was also the case for her less-skilled teammates (e.g., substitute players), and it is possible that coaches treat their athletes differently depending on performance level. However, competent coaches are crucial in fostering both athletic progression and personal growth (25, 73). Coaches should not only be technically and tactically proficient but also engage in regular communication with their athletes in an open, clear, and constructive manner. Effectively guiding sports talents also involves preparing them for the rigors and standards of elite senior-level competition by gradually introducing relevant expectations and challenges (73). The success of coaching depends not solely on the coach or the athlete individually, but rather on the dynamic and collaborative relationship they establish. This relationship serves as a crucial foundation for fostering motivation, confidence, satisfaction, and support, ultimately contributing to enhanced performance, a positive sporting experience, and the overall well-being of both parties (73). It has also been argued that the judgements, decisions, and adjustments arising from a well-functioning athlete-coach interplay represent the core of optimizing training quality (74, 75).

The performance level of teammates and opponents represents a critical environmental factor in the talent development process within team sports. In the present study, the player proactively pursued higher-level training environments in line with her advancing performance level. Training alongside or competing against more skilled athletes increases task complexity and fosters accelerated learning and adaptation (22). Through the process of co-adaptation, athletes must acquire new skills or strategies to continuously challenge their opponents with new problems. In essence, they are required to constantly reinvent themselves or demonstrate the capacity to adapt to the evolving strategies employed by their competitors (22). Conversely, training with or competing against less proficient opponents over time can constrain performance development by failing to provide an adequate stimulus for growth. It is therefore crucial to find the optimal challenge level. By deliberately managing the performance standard of teammates and opponents, talent development can be optimized, leading to athletes who are technically proficient, tactically adaptable, mentally resilient, and socially competent. In the present case, the player and her performance team appear to have effectively orchestrated this dimension of the developmental environment.

Besides coaches and teammates, the support staff forms a highly important resource within a talent development environment (76, 77). Having access to educated helpers who can provide an excellent standard of support in everyday life and especially in challenging times, promotes athletes' chances of successful development (78–80). The player specifically emphasized the support she received from a specialist at the Olympic training center in modifying her physical training, as well as from a coaching expert who helped her clarify her thoughts and define her role as captain of the national team. The findings of this study further underscore the critical role of effective collaboration and communication among all stakeholders, including the athlete, coaches, medical staff, club, educational institutions, and national federation, in facilitating long-term athlete development. In general, the training and development process observed in the present study align with key principles presented in existing talent development frameworks (21–28, 30, 52, 59).

Some study limitations need to be addressed. Whereas previous research on talent development typically relies on either quantitative or qualitative methods (22), this study sought to integrate both approaches. For the qualitative component, we evaluated the study using Tracy's eight key markers of quality (81): (a) worthy topic, (b) rich rigor, (c) sincerity, (d) credibility, (e) resonance, (f) significant contribution, (g) ethics, and (h) meaningful coherence. As outlined in the introduction, the topic is considered worthy as it addresses important questions concerning the training and development process of a world-class handball player. We sought to ensure rigor, sincerity, and credibility by combining established methods of data collection that generated rich qualitative and quantitative material from multiple perspectives; conducting thorough review and negotiation processes to confirm accuracy and resonance; and maintaining transparency regarding methodological procedures and limitations. We regard the study as making a valuable contribution to both scientific knowledge and applied practice. Ethical considerations included obtaining formal approval for the research and adopting respectful practices to safeguard a collaborative relationship between researchers and participants. Although all participants were anonymized, they were aware that they could potentially be identified based on the information presented in the study, and they consented to participate under these conditions. Meaningful coherence was obtained by adhering to the intended project design, with alignment of study aims, epistemology, conceptual frameworks, methodology, and presentation of findings.

A common challenge in case studies focusing on training content is ensuring the accuracy and validity of the data. Nonetheless, elite performers and teams generally maintain systematic and precise records of training activities, supporting the use of training logs as reliable primary or secondary sources in scientific investigations of training characteristics (48, 49, 82, 83).

To mitigate bias and misinterpretation, we incorporated triangulation across methods, data sources, and investigators. We observed a high degree of consistency between the player and the respective coaches in terms of retrospective data related to the practice of training, athlete characteristics and environmental factors. However, it remains possible that parts of this story may have been nuanced if other informants (e.g., teammates or other coaches) were included. Moreover, accurately assessing training load remains challenging due to the intermittent nature of handball, and recorded time is not necessarily the most appropriate approach because of recoveries and fluctuations in intensity. Indeed, more detailed information on the training load from handball-specific sessions could potentially contribute to a more comprehensive understanding of an athlete's career trajectory. Another caution is related to the large variation in pathways to success (21–28), as several roads may lead to Rome. Many handball players have engaged in similar training regimens during childhood and adolescence without reaching the same level of success. Therefore, the findings should be interpreted carefully, as no causal relationships can be established.

The authors' professional background, including former and/or present leading positions within the Norwegian Olympic Federation and acknowledged high schools with a sports program, is both a strength and a potential source of bias. Collectively, the research team has over three decades of experience working with elite athletes and talents, including world-class handball players. This expertise provided unique access and contextual understanding, enhancing our capacity to collect and interpret the data. However, we also acknowledge that this familiarity may have influenced our interpretations.