Youth athletic development: An evidenced-based approach

Thomas Stringwell discusses the need for physical activity and sport participation in youth populations.

A recent survey carried out by Sport England demonstrated that daily physical activity among youth populations within the UK has risen by 3.6%, with peak activity levels occurring between the ages of five and seven, and again between the ages of 11 and 12, across primary and secondary school education¹. The reported increases in participation were driven by out-of-school activities, including active play (predominantly years one to six) and, later, team sport activities (predominantly year seven onwards).

The benefits of such physical activity and sport participation in youth populations is multifaceted, with many physical, psychological and social benefits being reported in literature including increases in aerobic capacity, bone health and muscular development², alleviated symptoms of depression, stress and anxiety³, higher self-perception⁴, better emotion regulation, interpersonal skills and an increased ability to develop good-quality peer relationships⁵. Additionally, early sport participation has been shown to have a positive impact on life skills in adolescents, including goal setting, time management and problem solving⁶. It is therefore evident that physical activity and sport participation in youth populations serves a vital purpose, not only for physical health but for society as a whole. Furthermore, it is apparent that those working or involved in physical education or youth sport have a large responsibility to ensure any implemented physical activity is well structured, follows current research guidelines and encourages future sport/physical activity participation, allowing for the next generation to reap the wide variety of physical, psychological and social rewards that sport and exercise provides.

Increasing robustness and athletic readiness

Despite the many benefits associated with youth sport and physical activity participation, there is also an apparent injury risk when partaking in such activities, with an estimated 1.3 million children (under the age of 15) being treated in hospital for sport-related injuries across the EU annually⁷. From the data analysed, team sports accounted for approximately 40% of the sport-related hospital-treated injuries, most likely due to their popularity and movement demands. Much like their adult equivalents, youth team sport athletes are still required to perform repeated changes of direction, sprints, jumps, landings and many other forms of explosive movements, all often in reaction to a stimulus and the chaotic demands of their sport while under fatigue^8-12. Hence, the biomechanical and physiological demands of competitive youth sport require adequate athletic preparation, ensuring youth athletes are physically prepared for the demands of their sport. Such youth athletic preparation is well established within elite sport academies, organisations and Varsity High Schools^13-16. However, not all youth populations will be fortunate enough to experience such well-structured youth strength and conditioning programmes, therefore potentially being unprepared for the demands of youth competitive sport¹⁷. Such a lack of readiness and robustness may place youth athletes at a higher risk of injury or disengagement in future sport participation, therefore potentially missing out on the many physical, psychological and social benefits that physical activity and youth sport can provide. Indeed, it has recently been suggested that the secondary school education system within the UK provides a great opportunity for strength and conditioning practices to be integrated within physical educational curriculums, not only for youth athletes but for youth populations as a whole¹⁸. Such an integration would provide youth populations with a greater level of physical literacy and overall movement quality, resulting in a greater level of sport participation both in youthhood and in later adult life.

Myths surrounding youth athletic development

One barrier to application of youth strength and conditioning is the unfortunate misunderstanding regarding the effects of resistance training within youth populations, with potential injury to growth plate fractures often being cited as a high-risk factor¹⁹. However, contrary to such beliefs, evidence suggests that resistance training in youth populations actually increases bone mineral content, bone strength index and cortical bone area¹⁹. Furthermore, resistance training in adolescent females has been shown to have positive effects on bone health later in life, reducing osteopenia and the risk of osteoporosis²⁰. In addition to the positive effects on skeletal health, resistance training in youth populations has been shown to enhance neuromuscular control, increase muscle fibre size and tendon cross-sectional area¹⁹. Hence, the morphological and mechanical adaptations to the skeletal and neuromuscular system brought about by resistance training in youth populations not only have a positive effect on future athleticism, but also on overall health and wellbeing.

Interestingly, research findings suggest youth populations are at a greater risk of injury when partaking in sport vs resistance-training activities, with a recorded injury occurring in 20% of youth athletes partaking in sport vs 0.7% of those partaking in resistance training²¹. It could be argued that the greater injury rates observed could be accounted for due to the greater popularity of youth sport participation vs resistance training. However, with the previously highlighted biomechanical demands of youth sport, it could also be argued that, with an equal amount of youth athletes partaking in sport and resistance training activities, such greater injury rates would still be observed within sport participation, due to the greater risk of injury occurrence from landing, braking, changing direction, collisions and the general chaotic nature of sport. It is therefore apparent that the myths surrounding resistance training in youth populations are unjust and could actually lead to youth athletes missing out on the many physiological benefits brought about by resistance training. Hence, resistance training in youth populations should be encouraged rather than discouraged and even embedded within physical education programmes.

Laying a foundation of physical literacy

Despite the numerous benefits of resistance training in youth populations, it is imperative that any planned resistance training is laid upon a solid foundation of good movement quality. Hence, the initial and continual aim when coaching youth populations is to embed physical literacy while exploring new movement qualities. Such an expansion of movement vocabulary ensures a child develops a full range of motor skills, providing a bedrock for future specialisation within their later chosen sport²². Indeed, research demonstrates that adult world-class athletes partook in early multisport practice, specialised within their chosen sport later within their athletic development, accumulated less main-sport practice and progressed at a slower rate compared to national-class athletes²³. These findings demonstrate the later performance risks of earlier specialisation within youth populations. Furthermore, such early specialisation can lead to a disengagement in sport participation. Pre-adolescent children have a reduced attention span, meaning training needs to be fun, interactive, less regimented and engaging. Such a multi-sport approach results in greater athletic sustainability and long-term athletic development and, ultimately, a more successful competitive sporting career²³. It is therefore evident that the earlier stages of youth athletic development should focus on expanding physical literacy, introducing children to a wide variety of sporting and physical activities while avoiding early specialisation, with any planned activities within the early stages of youth athletic development being fun, interactive and engaging.

Biological age vs chronological age

Another key consideration when training youth populations is biological age vs chronological age. Where the chronological age of two youth athletes may be the same, their biological age can vary greatly, with the onset of adolescence occurring at different times between individuals²⁴. One such way that maturational development can be quantified within youth populations is by measuring the rate of growth height or peak height velocity (PHV), with PHV being defined as the greatest change in vertical growth height²⁵. This normally occurs between the ages of approximately 10 and 11 in girls and 12 and 13 in boys and indicates the onset of puberty and is accompanied with large increases in anabolic hormone concentrations^25-27. If a youth athlete has developed a solid foundation of physical literacy prior to reaching PHV, meaning that individual can effectively jump, land, squat, lunge, hinge, push, pull and biomechanically optimally, then such a young athlete is primed to reap the rewards of the favourable anabolic hormonal drive that occurs during adolescence. Hence, with a well-structured performance programme that applies simple progressive overload and a constant reinforcement of good movement quality, such a youth athlete has the potential to gain progressive neuromuscular adaptations throughout adolescence, resulting in increases in athletic performance and robustness to injury²⁸.

Long-term athletic development

Based on the previous findings presented, it is apparent that any proposed youth athletic development performance model has to consider the maturational development, psychological development, social development, individual movement skills and levels of physical literacy of any individual youth athlete. To address all these factors, Balyi and Hamilton (2004) at the Canadian Institute proposed the Long-Term Athletic Development Model (LTAD), which has since been applied across many major sporting bodies worldwide²⁹. The LTAD model separates the development of youth athletes through to senior athletes into seven separate stages (Figure 1) with the first two stages (active start and FUNdamentals) focusing on embedding physical literacy, non-early specialisation and exploration of multi-sport movement qualities. This embedding of good movement quality primes the youth athlete for the third ‘learn to train’ stage and the rapid neuro-adaptations that occur, resulting in a fine tuning of motor skills.

Such positive motor skill development primes the youth athlete for the next key ‘window of opportunity’ between the ‘learn to train’ and ‘train to train’ stages, with opportunity arising for rapid neuromuscular adaptations (e.g., strength and power development) at the onset of PHV and adolescence. Throughout these key stages, the planned sport-specific training becomes gradually more specialised, with an increasing focus on social and psychological development. Within the final three stages (learn to compete, train to compete and train to win) the athlete progresses from a youth athlete to senior athlete, with a gradual increase in individual specialised training (on any physical and skill qualities that need specific improvement) and an increased focus on the psychological demands of competition²⁹. The introduction of the LTAD model was a key point within youth athletic development, providing a framework that considered a child’s maturational, neuromuscular and psychological development, while providing specific aims and proposed training approaches for each relative stage. Furthermore, the LTAD model highlighted the key stages upon which a youth athlete has the opportunity to rapidly accelerate certain physical qualities, therefore placing a key emphasis on the need for priming each of these key stages with a foundation of physical literacy and good movement quality. Hence, modern youth sport owes a great deal to the pioneering work of Balyi and Hamilton and the Canadian Institute of Sport.

The youth physical development model

Later within the evaluation of youth athletic development, researchers started to challenge certain aspects of the LTAD model. In particular, the specific suggestion that the development of certain specific qualities (e.g., strength and power) should be orientated around the previously described ‘windows of opportunity’ rather than being trained concurrently from the outset. This led to the development of the Youth Physical Development (YPD) model, formulated by Lloyd and Oliver (2012), arguably the most current, evidence-based approach to youth athletic development. The YPD model proposes that each training quality within youth populations can be trained concurrently, with each quality being logically progressed, the rate of which being dependent upon a child’s individual level of physical literacy, movement quality, neuromuscular and maturation development³⁰. Therefore, unlike the LTAD model, the YPD model doesn’t delay the introduction of certain training qualities until pre PHV and at the point of PHV, but rather allows each of these qualities to be developed simultaneously. Furthermore, the YPD model graphically distinguishes the concentration (e.g., volume, intensity, speed) of each training quality by the increasing the font size/cell colour shade. Maturational status (pre PHV, PHV and post PHV), training structure (unstructured progressed to very high structured), chronological age, age period and growth rate are also all graphically represented. Lastly, the differences between genders and the point at which PHV and adolescence occurs is accounted for. Such a conclusive model that compiles all the varying factors listed makes for an applicable, evidenced-based approach to youth athletic development (Figure 2).

The role of parents and coaches

The final piece of the youth athletic development performance puzzle to consider is the psychological and social development of a youth athlete or any child partaking in physical activity, and how our behaviour as coaches and parents can influence this process. Again, Lloyd and colleagues (2015) have hugely contributed to this aspect of youth athletic development, developing the Composite Youth Development Model, which modifies the YPD model slightly by adding a psycho-social development schematic, with an early focus on exploration and self-interaction, then peer relationships, empowerment and self-esteem, and finally self-worth and confidence for recreational sport participants and sport-specific psychological skills for elite competitive athletes (Figure 3)²⁹.

Indeed, research demonstrates that parents who display praise and understanding behaviours within youth soccer contribute the most towards a child’s teamwork, goal setting, leadership and total life skills³¹. Therefore, it is evident that our behaviours as parents and coaches have a great impact, not only on a child’s sporting career but also their overall psycho-social development. It is paramount that coaches don’t approach the training of a youth athlete like they are training a mini-adult, but rather consider the child’s maturation status, current movement quality, levels of physical literacy and their psycho-social status before implementing any form of performance programme. Lastly, we must remember that we are not only training a young athlete, but we are preparing a young individual for society and, therefore, have a big responsibility as coaches.

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