Sustainable performance plan development to prevent non-contact ACL injuries in youth and adolescent athletes: a clinical practice review

Introduction

The concept of “adolescence” traces its origins to the 15th century, derived from the Latin word “adolescere”, meaning “to grow up or to grow into maturity” (1). Due to the combined effects of rapid musculoskeletal growth, neurodevelopmental immaturity, and high levels of sports participation this stage is marked by increased vulnerability to overuse injuries, particularly among youth and adolescent athletes (2-5). However, there is no universal consensus on the precise age range that defines adolescence (6). Compared to adults, youth adolescent athletes experience greater susceptibility to sports-related injuries, which may have long-term consequences on health, behavior, and future participation in physical activity (2,7,8). Understanding the unique developmental challenges faced by this population is essential for implementing effective injury prevention and performance optimization strategies.

Higher-order frontal cortex executive function and lower-order interneuronal network connections continue to mature until young adulthood, influencing cognitive control, decision-making, and impulse regulation (9-12). In the context of sports, this ongoing neurodevelopment contributes to heightened susceptibility to boredom, poor self-control, excessive sports passion, and risk-prone behaviors, all of which may increase injury risk in youth and adolescent athletes (13-17). Additionally, the accumulated microtrauma associated with high volume sports training and competition may increase the risk of sudden anterior cruciate ligament (ACL) mechanical fatigue-related failure from non-contact mechanisms. In youth and adolescent athletes this mechanism may represent >70% of all ACL injuries (3). Over the past 20 years, the number of ACL ruptures in patients aged 6–18 years has increased by at least 2.3% per year, with higher rates in females aged 16 years and males aged 17 years (18). The increase in ACL injuries among children and adolescents has been attributed, in part, to increased participation in physical activities and sports, leading to a higher risk of injury. Concurrently, the developmental immaturity of both the brain and musculoskeletal systems of youth and adolescent athletes further increases the risk of concussions and other closed head injuries (19) which may indirectly contribute to ACL injury occurrence by impairing neuromuscular control and reaction time (20). Among athletically active youth and adolescent girls, a combination of biomechanical alignment issues, femoral and tibial morphology, weak core strength, impaired neuromuscular control, and menarche (monthly connective tissue mechanical property fluctuations and impaired neuromuscular control) further increase ACL injury risk (21). Youth and adolescent athletes who train for more hours in their sport each week than their age in years (odds ratio =2.07) or whose ratio of organized sport to free play time exceeds 2.1 hours/week (odds ratio =1.87) have a greater serious overuse injury risk (22). By incorporating sustainable performance planning strategies, training loads may be more effectively balanced, helping to reduce injury risk while optimizing long-term athlete development (6).

Rationale and knowledge gap

Youth and adolescent athlete sport participation has moved away from unstructured free play during or after school to more structured, skill-based, and private sector-driven club sport activities (4). While this transition has fostered early talent development and competitive opportunities, the number of knee injuries has increased, leading a growing number of youth and adolescent athletes to discontinue sports participation (4). As youth sports continue to emphasize specialization and elite-level training, there is a growing need to better integrate injury prevention strategies within performance training and skill development frameworks (5). However, for these approaches to be effective, they must be adapted to the unique developmental, psychological, and cultural factors that influence youth and adolescent athletes’ participation and compliance (23). Addressing these challenges through contextually relevant, athlete-centered strategies may help optimize long-term participation, injury prevention, and performance outcomes.

Objective

This clinical practice review explores the impact of elite sports training programs and early specialization on youth and adolescent athletes, with a specific focus on non-contact mechanical fatigue-related ACL injury risk. By synthesizing current evidence, we aim to highlight the importance of sustainable performance plans, which incorporate active rest and recovery, boredom mitigation, and self-control development as potential strategies to enhance injury prevention program compliance. A comprehensive literature review was conducted using PubMed, Web of Science, OVID MEDLINE database searches synthesized into the following sub-sections: The elite training industry and rise of specialization; Lessons from sports diversity and delayed specialization; Developing more than muscles; Mitigating boredom, developing self-control; Active rest and recovery; Culture, context, and compliance; and Blending performance training and injury prevention. These sections provide a structured overview of current challenges and opportunities for optimizing both sports performance and injury prevention for developing athletes.

The elite training industry and rise of specialization

In the USA, the youth and adolescent sports industry represents a $30 billion dollar business (24), which is projected to increase to $70 billion by 2030 (25). Although poorly defined, a component of this industry is elite training programs (26), which are generally associated with greater total training volume, more frequent, higher level, and more intense competitions (27).

Elite training programs have increased in popularity as many youth or adolescent athletes perceive early specialization as necessary for obtaining a college athletic scholarship or playing for a select club or Olympic development team (28). This belief often leads parents to encourage early specialization, sometime enrolling their children on travel teams at a young age (29). The likelihood of a scholarship, however, is minuscule (28,29), with the odds of obtaining an National Collegiate Athletics Association (NCAA) sports scholarship being <2% (4,29) and the average annual amount being <$11,000 (30).

The concept of elite training volume is often linked to Ericsson’s “10-year or 10,000-hour rule”, which suggests that achieving expertise in any domain requires a decade of deliberate practice (31). However, it is crucial to distinguish between structured, goal oriented training designed to enhance performance and the high-intensity, repetitive mechanical loading frequently seen in youth sports training (32). The 10-year or 10,000 practice hour rule was based on studies of small groups of musicians and chess players, not on the multitudes of youth and adolescent athletes who regularly participate in high total volume (intensity, frequency, and/or duration) sports practices. Studies of youth and adolescent athletes have shown that early specialization before pubertal maturation is not a guarantor of sports success and, in many cases, may be detrimental to long-term achievement because of overuse injury, burnout, social isolation, or premature athletic foreclosure (15,33-36). From a public health perspective, one of the most concerning outcomes of early sports dropout is the increased risk of long-term physical inactivity, which may contribute to obesity, cardiovascular disease, and other chronic health conditions in adulthood (11,34-36).

Elite training programs have been associated with higher injury rates compared to traditional sports participation, particularly during the critical developmental period of youth and adolescence (2,33,36-39). Despite the increased injury risk, many youth sports programs operate with fewer medical and rehabilitative resources compared to higher-level collegiate and professional sport organizations (37,38). This discrepancy highlights the need for a more comprehensive healthcare approach that prioritizes collaboration, shared responsibility, and open communication among all stakeholders, including, coaches, parents, medical professionals, sports physiotherapists and athletic trainers (40). While parents desire what is best for their child, they and the coaches and other essential stakeholders who advise them, may lack an understanding of how vulnerable tissues such as ligaments are during youth and adolescent sports participation (41-46). Without proper guidance, early specialization and intensive training may inadvertently increase long-term injury and sports attrition risk. To promote both injury prevention and long-term athlete health there is a growing need for sustainable performance plan development that balances skill acquisition, physical conditioning, and structured active rest and recovery strategies.

Lessons from sports diversity and delayed specialization

Without the opportunity to sample a variety of different childhood sports, young athletes are less likely to develop the foundational physical, psychosocial, cognitive, and coping skills needed for optimal sport success (47) and long-term adult health (5). Opportunities for early multisport participation, however, have diminished, as structured, single-sport specialization has become more prevalent. Participation in organized physical education programs has been shown to enhance physical health literacy, promote understanding of multiple sports, and improve overall physical fitness. Despite these benefits, the availability of structured physical education programs in schools has declined, limiting access to these developmental opportunities for many youth athletes (48). Given these challenges, coach educators are pivotal in promoting age-appropriate training adaptations, guiding policy development, and implementing sustainable performance strategies (48,49). Integrating sports diversity principles and structured, developmentally appropriate training models into youth athletics may mitigate the risks associated with early specialization while fostering greater long-term engagement in sports and physical activity.

In reviewing 3,090 athletes from high school, college, and professional teams, Buckley et al. (22) reported that specialization age was lower for high school athletes (12.7±2.4 years) compared to college (14.8±2.5 years) and professional (14.1±2.8 years) athletes, supporting the notion that earlier specialization generally did not necessarily translate to an increased performance level. There are many examples of athletes who eventually became a champion after a relatively short training period or changed their sport as part of a talent crossover or recycling program (50).

In a jump-landing task study of over 350 athletes between 8-to-14 years of age, multiple sport athletes were 2.5 times more likely to possess good jump landing control than single sport athletes (51). Additionally, a cohort study of specialized female soccer, volleyball, and basketball athletes compared with non-specialized athletes found that specialized athletes displayed more abnormal drop-vertical jump task landing mechanics with increased contact forces and diminished impact force absorption strategies as evidenced by greater hip and knee kinematic variability, suggesting greater knee injury risk (52). From a sustainable performance planning perspective, these findings highlight an opportunity for coaches to incorporate greater task diversity and adjust training loads to replicate the developmental benefits of multi-sport participation. By integrating structured movement pattern variability and neuromuscular training, sports program may better mitigate injury risk while optimizing athletic development.

Developing more than muscles

In addition to the improved teamwork, sportsmanship, physical strength, endurance, power, and greater bone density that develops with youth and adolescent sports participation, important lifetime cognitive, affective, social, and moral domain growth also takes place (53). Engaging in structured athletic activities helps young athletes develop life skills such as resilience, discipline, and emotional regulation, which extend far beyond the playing field. Despite these benefits, the pediatric medical community is increasingly challenged by the growing adolescent population, with the age range for adolescence continuing to expand (54). Worldwide, pediatricians are concerned that the range of existing services needed to provide effective adolescent healthcare are insufficient (54), with a call for stakeholders such as coaches, educators, parents, and healthcare professionals to support them in combating this growing public health concern (55,56). Given that some youth athletes begin elite training as early as age 12 years—or even younger—it is imperative to prioritize their health, safety, and overall well-being (57). Implementing sustainable performance strategies that balance physical development with mental and emotional well-being can help mitigate the risks associated with early specialization, overtraining, and long-term injury susceptibility.

The transition to elite-level sports participation occurs during a critical period of psychosocial and emotional development, coinciding with an increased risk for mental health challenges such as burnout, anxiety, and identity foreclosure (57,58). Research suggests that youth and adolescent athletes with a strong athletic identity may be more vulnerable to psychological distress, particularly if they lack strategies to navigate the demands of elite training (57). A study examining mental health literacy in young athletes highlights its role in enhancing self-esteem, motivation, and sports enjoyment (57). Evidence also suggests that early recognition of mental health symptoms, coupled with accessible psychological support, can reduce the risk of early dropout and negative long-term outcomes (57). Autonomy in training may also play a role in mental well-being and motivation. Research on self-determination theory in youth sports suggests that athletes who feel a sense of control over their training schedules and personal goals report higher levels of intrinsic motivation and lower levels of stress (14,57). However, complete autonomy at a young age may not always be developmentally appropriate, as a study suggests that structured guidance from coaches and educators remains essential for balancing training intensity, recovery, and academic or personal commitments (57).

Having an effective multi-disciplinary healthcare model with teamwork between diverse healthcare providers, coaches, educators, parents, and athletes is essential, but models such as these are more common at higher-level professional and Division I NCAA sports training environments than within the context of youth and adolescent sports. As the youth and adolescent sport athlete transitions to elite level training, changes in diet, sleep, training load, housing, extended travel, reduced social network connections, increased performance pressure, involvement with already established teams, coaches, high performance support staff, and teammates, can create complex demands that challenge mental health (57). Additionally, adapting to pre-existing team dynamics and interactions with experienced teammates, coaches, and high-performance support staff can contribute to psychosocial stress and mental health challenges. Given that these athletes are at an elevated risk for non-contact knee injuries, there is increasing interest in how active rest and recovery strategies can be effectively integrated into sustainable performance planning. Research suggests that optimal development requires a balance between structured training, adequate recovery, and psychosocial support systems (57). To create a safe and supportive environment, sports organizations must address both internal and external factors influencing athlete well-being. Within the sport system, this includes fostering positive athlete-coach relationships and promoting individual coping strategies. Beyond the sports environment, maintaining family and peer connections, as well as supporting non-athletic interests and identities, has been associated with greater athlete resilience and long-term engagement in sports participation.

Mitigating boredom, developing self-control

Youth and adolescent athletes often have a strong, exclusive athletic identity and a high, sometimes obsessive sports passion, being more likely to be boredom prone and displaying poor self-control compared to adult athletes (14-16). Research suggests that these youth and adolescents’ athletes who are prone to boredom have an increased risk of engaging in maladaptive behaviors including, smoking, drinking, illegal drugs, substance abuse, depression, anxiety or stress, anger and aggression, eating disorders or unhealthy food consumption, and cell phone or social media site addiction (14). Strong connections between cortical and subcortical brain regions, formed during motor skill acquisition, play a critical role in adolescent brain development. These linkages are essential for mitigating boredom and fostering self-control (14,59,60). Because of their individualized need to identify something they perceive as important or meaningful, boredom-prone youth and adolescent sports athletes may be more likely to either over-train (continued non-stop high intensity sports training) or under-train (substituting social media, cell phone, multiple “screen time” activities). In either instance, the ACL may be at greater injury risk either from chronic extracellular matrix (ECM) weakening from frequent over-loading or under-loading (41). Studies indicate that athletes who experience intrinsic motivation and enjoyment from structured sports participation are more likely to develop self-control, competence, autonomy, and relatedness, which are essential for psychological well-being and long-term adherence to injury prevention programs (53,61). By improving self-control (the antithesis to boredom), effective, sustainable performance plans can reduce injury risk concurrently with improved sports performance, thereby increasing the likelihood of enhanced healthcare outcomes during adulthood (13,14,17,62).

Active rest and recovery

To facilitate or enhance post-training physiological and psychological recovery, the active rest and recovery component of a sustainable performance plan may include a wide variety of submaximal effort running, jogging, cycling, swimming, stretching, and mind-body relaxation activities. Supplemental active rest and recovery modalities may include, but are not limited to, cryotherapy, thermotherapy, massage, sound, light, vibration, electrical stimulation, hyperbaric oxygen, and compression garments (63-65).

Active rest and recovery increase the tissue blood flow that delivers cell nutrients, removes waste products, increases local muscle energy stores, facilitates connective tissue healing and remodeling, and reduces delayed onset muscle soreness. Therefore, post-training, active rest and recovery is essential to physiological homeostasis restoration (64). It is important to note that active rest and recovery does not necessarily require a complete break from training. Instead, on designated recovery days, intense training loads such as full speed jumping, jump landings, and high-speed running directional changes with sudden acceleration and deceleration are reduced. In their place, lower intensity neuromuscular control exercises and submaximal movement tasks are incorporated to promote injury prevention and movement efficiency (38,66) (Figures 1,2).

Figure 1 “Follow the leader” low intensity group functional dynamic knee stability neuromuscular control task series on natural grass wearing sport cleats. This image is published with the participants’ consent.

Figure 2 Low intensity, no impact alternating knee to chest neuromuscular control task with eyes closed (exteroreceptive denial) on a stability pad. This image is published with the participant’s consent.

Ligaments are more susceptible to the effects of accumulated microtrauma (42) due to their comparatively lesser blood supply and more anaerobic metabolic activity compared to muscles. To more effectively prevent non-contact mechanical-fatigue related ACL injuries, growing evidence supports the need for more dedicated active rest and recovery between elite training sessions and competitions (41,42). Providing the ACL with adequate recovery time allows for ECM deposition and tissue remodeling, which are essential for maintaining tissue mechanical integrity (7). Without sufficient recovery, the cumulative stress on the ACL may contribute to progressive structural weakening and increased injury risk. Beyond neuromuscular control and game strategy planning, active rest and recovery protocols should emphasize low-to-moderate intensity activities, such as straight-ahead running, to support aerobic function, circulatory nutrient delivery, and technical skill development. These targeted approaches can contribute to both performance optimization and long-term joint health.

A comprehensive sustainable performance plan should aim to enhance the youth and adolescent athletes’ understanding of the importance of active rest and recovery to both prevent overuse injuries and to better sustain performance. For this to occur, however, the athlete must intermittently avoid incessant high-intensity, frequency, or duration training loads. To better restore physiological and psychological system homeostasis one approach involves coaches strategically adjusting practices to better integrate the maintenance loads that prevent de-training with vital active rest and recovery injury prevention and performance factors (i.e., self-control, neuromuscular control development) (67). This balance between training intensity and recovery has been described as the “Holy Grail” of safe sports training, highlighting the complexity of optimizing both performance and injury prevention (37). In addition to adjusting training loads to improve conditioning or skill development, research suggests that more holistic training should also develop the neuromuscular control, neurocognitive and visual-motor system function, and self-control that supports ACL ECM homeostasis. Ideally, this occurs under the encouragement and guided feedback from a skilled coach, educator, or parent. Despite the recognized benefits of active rest and recovery, many youth and adolescent athletes do not obtain sufficient recovery between intense training sessions or competitions placing the ACL at increased non-contact mechanical fatigue-related injury risk (41,42). In coaching, the term “sustenance” refers to strategies to maximize general and specific athlete well-being through recovery and regeneration in between more intense training intervals or competitions (6,41-46,67). Active rest and recovery post-training helps shift the athlete from physiological fatigue-related metabolic disturbances toward the homeostasis that facilitates greater tissue healing and remodeling before subsequent exertions thereby improving sustainable high training load tolerance (63,64).

Culture, context, and compliance

Although neuromuscular control training programs can significantly reduce non-contact ACL injuries (67,68) their implementation remains inconsistent, and athlete compliance is often suboptimal (68-71). Research suggests that these programs may also enhance sports performance, a benefit that could encourage greater adoption among coaches and athletes, particularly because these interventions pose minimal or no injury risk (70,72). Several studies, however, have reported issues related to achieving athlete compliance with these interventions (73-76). In a study of amateur soccer players ≥14 years of age, Lindblom et al. (77) reported that players were pleased that injury prevention programs reduced injuries; but they disliked that the activities were boring and took valuable time away from soccer practice. This highlights the importance of integrating coaches into the implementation process, as coach involvement may increase the youth and adolescent athlete’s perception of these programs being both valid and highly important. A randomized study of high-level under 11 and under 14 years of age soccer players (n=1,403) who participated in a coach-led 20-minute duration, 7 neuromuscular training task sessions 2–3 times/week focusing on motor skills and movement quality reported a 32% reduction in non-contact lower extremity injuries compared to players who performed a standard warm-up (78). The authors further suggested that the observed results would have been even better with greater athlete compliance (78). These findings strongly support the efficacy of sustainable performance plans being developed and implemented with coach involvement.

To effectively implement a sustainable performance plan for the purpose of preventing non-contact mechanical fatigue-related ACL injuries in youth and adolescent athletes it is essential to possess a sound understanding of potentially injurious mechanisms (e.g., poor lower extremity kinematics during single-leg jump landings or running directional changes), the context (e.g., athletes practicing on an athletic field after school), and obtain input from all stakeholders, particularly athletes, coaches, educators, parents and healthcare professionals (72). In interviews with Belgian Olympic athletes and staff, Bonell Monsonís et al. (72) determined that injury prevention strategies should include nutritional information, emphasize both physical and mental health, and teach athletes about the injury potential associated with over- or under-training. Experienced elite athletes acknowledged that they assumed primary injury prevention responsibility by caring for and listening to their bodies (72). However, they also suggested that in the elite training context, all athletes should have access to qualified, specialized coaching and sports healthcare professionals within a culture of high injury prevention importance. Despite the potential benefits of multidisciplinary healthcare teams, these resources are not typically available in youth and adolescent sport settings, particularly in cases of elite training and early specialization. A study suggests that regular and effective communication between athletes, parents, and coaches, and between athletes, parents, and sports healthcare professionals is crucial to creating the trusting relationships that facilitate plan compliance (72). So that younger athletes develop appropriate habits and expectations regarding injury prevention awareness and education prior to injury, older, experienced athletes stated that injury prevention strategies should be introduced early during athlete development (72). Experienced athletes also advocated the importance of teams, clubs, and organizations supplying adequate facility and personnel resources (72), which are less likely available in many youth and adolescent sports settings.

Ericsson’s (31) concept of deliberately planned practice adjustments is harmonious with active rest and recovery principles, emphasizing the strategic balance between training intensity and recovery to optimize athletic development (6). In the youth and adolescent sports environment, however, coaches often face competing priorities, as their focus on winning, skill development, and conditioning may create a potential conflict of interest when considering the long-term benefits of structured recovery (6). Inadvertently, the responsibility of effectively monitoring adolescent athlete training volume (intensity, frequency, duration, and total volume) often may fall upon the opinion of the youth or adolescent athlete. Although this input is important, research suggests that the high, and sometimes obsessive, sports passion (15,16) and immature reasoning skills (9-12) of most youth and adolescent athletes does not bode well for them being the primary information source regarding safe sports training or competition volume decisions (6).

Implementing a sustainable performance plan with an existing sports culture can be challenging. Even when key stakeholders acknowledge the benefits of such an approach, successful adoption and compliance may be hindered by cultural barriers and context-specific challenges (23). Another possible concern might be that many sports cultures have traditionally placed high, almost singular value on toughness and stoicism (57). Although this may sometimes prove helpful during competition, when applied to all situations, it risks creating the impression that mental health concerns are less important, leading those who might benefit most to not seek care (57). Research highlights the importance of creating psychologically and physiologically safe team environments, where trust, mutual respect, and acceptance of mistakes foster long-term athlete development and well-being (34). Effectively blending the right balance of personal, environmental, societal, and sports-specific program delivery factors is an important part of sustainable performance plan development, implementation, and compliance (34). Rather than focusing solely on injury mechanisms, the plan should be designed to address the holistic and comprehensive needs of each athlete or athlete group, ensuring a more inclusive and effective approach to long-term sports participation and injury prevention (8).

Blending performance training and injury prevention

To enhance the implementation and compliance of youth and adolescent injury prevention programs it is essential to promote the concept of sustainable performance. Case studies illustrate the impact of excessive training loads and inadequate recovery on injury risk. For example, a 13-year-old softball pitcher who, in addition to team play, concurrently performs specialized training to increase pitch velocity, in the process sustaining a superior labrum anterior and posterior (SLAP) lesion; the case of a 15-year-old volleyball outside hitter who supplements team play concurrently with specialized training to improve vertical jump magnitude, developing degenerative patellar tendinosis in the process; and the case of a 17-year-old soccer player who plays concurrently for both high school and club teams sustaining a non-contact ACL tear. In the presence of biomechanically sound sports movements, appropriate nutrition, and sleep, one might accurately surmise that some component of excessive sports training loading (intensity, frequency, duration, total volume) and/or under-recovery likely contributed to each of these injuries. In all cases, these athletes were treated surgically and, after comprehensive physical therapy, returned to their sport. However, two years later, none continued playing their respective sports. In addition to other potential factors, some combination of fear, diminished performance capabilities, recurrent pain or other injury symptoms or burnout may have contributed to this outcome (58). Research suggests that contextually relevant, deliberate active rest and recovery strategies, when integrated into a sustainable performance plan, may help reduce injury risk and promote longer athletic engagement (57). Athletes who follow structured recovery protocols and workload management strategies may be more likely to continue participation by choice, rather than being forced into early sport discontinuation due to injury and surgical intervention (15,58) (Figure 3).

Figure 3 Active rest and recovery to restore ECM homeostasis and reduce non-contact mechanical fatigue-related ACL injuries (green arrows). ACL, anterior cruciate ligament; ECM, extracellular matrix.

As part of sustainable performance plan development, fostering collaborative discussion among youth and adolescent sports coaches may enhance training and competition management from an active rest and recovery standpoint. Advisory panels, where coaches from different sport disciplines exchange perspectives on workload management, injury prevention, and recovery strategies, could help mitigate sport-specific biases and promote a more balanced approach to athlete development. By stepping outside their own unique sport cultures, coaches may be better equipped to integrate sustainable performance principles across various sports settings.

In contrast to older, more experienced, higher-level athletes who understand that they have a personal responsibility for sports injury prevention program compliance, younger, less experienced athletes generally assume less responsibility and need greater instructional guidance with enforced oversight (72). Previous studies support the idea that successful sustainable performance plan implementation requires close cooperation, open communication, involvement, and shared supervision from all stakeholders who support the youth and adolescent athlete (57,72) (Figure 4).

Figure 4 Successful blending of sport performance and injury prevention in youth and adolescent athletes creates sustainable performance.

In addition to current student educational objectives, with more than 1.3 billion primary and secondary school students worldwide (79), existing school resources (both personnel and facilities) may represent a good environment to help improve youth and adolescent athlete public health (80). Successful coaches better meet the demands of their own unique environment by adapting their behaviors (81), assuming personal responsibility for holistic youth and adolescent athlete development beyond solely focusing on sports skill development or conditioning, instilling the importance that each athlete assume some personal responsibility to contribute to their own learning and injury prevention (82). To achieve sustainable performance while on select days decreasing ACL microtrauma accumulation risk, successful coaches deliberately adjust sports training, placing greater importance on movement skill or task quality than quantity (83,84). The same technological advances, nutritional innovations, and improved understanding of biomechanics that enhance sports performance can also improve sports injury prevention. Even small concessions to injury prevention to better accommodate uninterrupted sustainable performance increases the likelihood that a youth or adolescent athlete better maintains long-term sport performance while avoiding the over-training that leads to injury, burnout, or early athletic foreclosure (83-85). Effective coaches help individual youth and adolescent athletes balance training factors as they identify their own personal formula for success in their sports and in life (83).

Although sports performance and injury prevention concepts and personnel have long co-existed, the open communication and teamwork needed to concurrently improve both sports performance and injury prevention for many youth and adolescent athletes is lacking. To date, this balanced optimization has primarily been realized only with higher-level professional or NCAA Division I college sport teams where shared coaching and healthcare team oversight has teamed up to improve athlete health. One key barrier is the socioeconomic constraints that often limit access to comprehensive, multidisciplinary healthcare teams with expertise in injury prevention, rehabilitation, nutrition, and performance optimization. These resource limitations disproportionately impact youth and adolescent athletic programs, where the close collaboration seen at elite levels does not always translate effectively to developing athletes. As a result, the responsibility of managing workload, recovery, and injury prevention often falls on parents, coaches, and the athletes themselves who may lack specialized knowledge or structured guidance. The unique physical, mental, emotional, social, psychobehavioral, and identity-related vulnerabilities of the youth and adolescent athletes who participate in elite sports training require more creative, sustainable performance plan development and implementation with parents, coaches, and the athletes themselves serving shared primary oversight roles (22,54-56).

Children are often first introduced to sports by their parents, who provide transportation and emotional and economic support, often modifying daily routines to better accommodate practices and competitions (86). Parents also influence their child’s commitment to and value perceptions regarding physical activity and sports (53). Research, however, suggests that excessive parental pressure may diminish the positive effects of sports participation. Among youth and adolescent athletes higher expectations or intense parental involvement have been associated with reduced enjoyment, decreased intrinsic motivation, elevated stress levels, and diminished psychological need satisfaction (87).

Coaches play a critical role in shaping the values, behaviors, and training habits of youth and adolescent athletes, making them key facilitators in the development and implementation of sustainable performance plans (70). Potential barriers to a coach successfully implementing such a program include a lack of knowledge about all potential benefits, having a limited understanding of sport-specific injuries, lacking expertise regarding what sport-specific injury prevention tasks to employ, or a perceived lack of time, resources, or interest (69-71).

Successful sustainable performance plan implementation does not require any special equipment. In addition to adjusting training and competition schedules, for ACL ECM homeostasis restoration purposes, any perceived void created by these adjustments can be filled with sport relevant tasks that challenge the athlete’s capacity to develop better neuromuscular control, improve active recovery and rest, better mitigate boredom, improve cognition, improve visual motor skills, and improve self-control. Research suggests that coaches who employ highly repetitive, unchanging training tasks that lack variability or easy adjustment potential may indirectly promote athlete boredom, burnout, and overuse injuries (35,88,89). Repetitious overexposure to a few select, high-intensity, frequency, or total volume movements without sufficient active rest and recovery can blunt motor skill development and reduce performance, simultaneously increasing injury risk (38,84). Coaches who are unyielding in practice task selection, sequencing, and volume are also more likely to disregard the athletes’ opinions, values, and thoughts, fostering limited support or interest from them, further increasing the boredom that contributes to poor decision-making, poor self-control development (62,87), and the promulgation of destructive behaviors (13,14). Boredom increases when the youth or adolescent athlete: (I) engages in monotonous tasks; (II) gets frustrated or develop negative moods; (III) are poorly motivated with limited teammate involvement; (IV) have to endure waiting periods between primary tasks; (V) lack clear objectives or awareness of upcoming competitions; (VI) have limited team activity participation; (VII) perceive limited empathy from coaches or teammates; or (VIII) experience delays or problems with access, transportation or equipment issues (89). Successful coaches blend physiological, technical, and mental aspects of recovery into a comprehensive, holistic training approach (66,90).

Within the context of athlete age, sport, training environment, and available resources, all stakeholders involved in youth and adolescent athlete healthcare should work collaboratively as a team to determine the most effective approach for balancing training demands, boredom control, and recovery strategies. Identifying “the lowest common denominators” for success in sustainable performance planning requires an adaptable, context specific approach that accounts for both individual athlete needs and environmental constraints. The “Goldilocks” zone represents the identification of the ideal combination of boredom control, self-control regulation, and sport-specific training task selection, representing more of a constantly changing, reflective, ongoing process rather than a fixed goal. To reduce boredom, improve attentional focus and self-control, and better facilitate active rest and recovery, coaches should adjust training tasks to identify the “best fit” for athletes within their own unique sports team context and environment (17). Integrating both simple and more complex tasks, inserting time limits, and modifying training task expectations may increase athlete engagement, reduce boredom, and enhance self-control and attentional focus (91). Conversely, when a task is too challenging, or the loading is too intense, occurring at too great a frequency, or at too high a total volume, it should be made easier and less time dependent. Ensuring an appropriate challenge level within an adaptable training environment may contribute to more effective athlete development, improved recovery, and sustained sports participation.

In contrast to the rehabilitation process, where an injured athlete generally progresses from smaller, less complicated tasks to progressively larger, more complex ones (92), sports training tasks can similarly be deconstructed into smaller ones to better facilitate skill acquisition and movement efficiency. To accommodate the needs of athletes with differing conditioning or skill levels sport training tasks should at least partially be selected based on instantaneous complexity adjustment ease. Research suggests that incorporating training variability through exposure duration, controlled repetitions, and heterogenous stimuli may reduce boredom, enhance self-control, and improve overall training plan effectiveness (17).

With each task they are asked to perform, youth or adolescent athletes weigh the effort needed to maintain attentional focus against the cost of boredom (93,94). Research suggests that self-control becomes more difficult and boredom increases when athletes perceive tasks as too easy or lacking an optimal challenge level (17). For primary ACL injury prevention training tasks should improve postural awareness and dynamic neuromuscular control, mitigate boredom, increase self-control, and provide more dedicated active rest and recovery (95,96). Specialized training may also possess a higher independent injury risk factor simply because youth and adolescent athletes have less free play or unstructured recreational exercise time. Consequently, incorporating guided free play (Figure 5), neuromuscular control training, and active rest and recovery should be sustainable performance plan components. To better determine their influence on non-contact mechanical fatigue-related ACL injury risk, future studies should evaluate the ratio of organized (structured) to unorganized (free play) activity. Examining how varying levels of structured and unstructured movement influence long-term injury outcomes may help refine athlete development models and sustainable performance strategies.

Figure 5 Low intensity, short duration exposure free-play with guided autonomy to improve athlete communication, teamwork, group decision-making and leadership during active rest and recovery. This image is published with the consent of all participants.

Strengths and limitations

Mechanical fatigue-related ACL injuries from accumulated microtrauma are a significant concern among youth and adolescent athletes, particularly those who specialize early and participate in elite type training programs. Comprehensive athlete development should extend beyond skill development and sport performance to also include injury prevention through compliance with active rest and recovery strategies with neuromuscular control training. To increase compliance and efficacy coach contributions to sustainable performance plan development and implementation is vital. A study strength is that this review combined an extensive breadth of contemporary evidence to make recommendations for blending sport performance training and injury prevention into sustainable performance plans. A review limitation was a lack of randomized control trials (78). To better accommodate diverse topics and search terms such as injury prevention, sport performance, coaching, boredom, self-control, sport specialization, elite training, athletic identity, behaviors, pediatrics and public health relevant to youth and adolescent athletes into a cohesive review a variety of article types was included. Greater rigor such as use of the Methodological Index for Non-randomized Studies (MINORS) score to assess study quality may have enabled a more focused review, however, the information synthesis needed to combine concepts and ideas from multiple disciplines into sustainable performance plan principles would have been lacking. To confirm sustainable performance plans that integrate active rest and recovery and neuromuscular training into blended sport performance and injury prevention plan efficacy, randomized controlled studies and well-designed prospective cohort studies are needed.

Conclusions

Although many professional sports teams and NCAA Division I college athletic programs have groups of coaches, healthcare professionals, nutritionists, strength and conditioning coaches, and sport psychologists who holistically monitor the training volume, performance levels, and injury prevention status of every athlete on every team, this concept does not often translate to the youth and adolescent athlete environment. After vetting all key stakeholders, a sustainable performance plan that includes boredom mitigation and self-control enhancement, neuromuscular control training, and active rest and recovery activities may decrease the frequency of non-contact mechanical fatigue-related ACL injuries in youth and adolescent athletes, particularly those who participate in elite training with early specialization.

Acknowledgments

The authors would like to thank all current and former coaches who keep practices interesting and safe.

Footnote

Peer Review File: Available at https://aoj.amegroups.com/article/view/10.21037/aoj-24-37/prf

Funding: None.

Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at https://aoj.amegroups.com/article/view/10.21037/aoj-24-37/coif). J.N. serves as an unpaid editorial board member of Annals of Joint from November 2024 to December 2026. The other authors have no conflicts of interest to declare.

Ethical Statement: The authors are accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved.

Open Access Statement: This is an Open Access article distributed in accordance with the Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International License (CC BY-NC-ND 4.0), which permits the non-commercial replication and distribution of the article with the strict proviso that no changes or edits are made and the original work is properly cited (including links to both the formal publication through the relevant DOI and the license). See: https://creativecommons.org/licenses/by-nc-nd/4.0/.

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