What Should Kids Train at Each Age? A Physician’s Guide to Youth Athletic Development
Table of Contents
Key Takeaways: What Should Kids Train at Each Age
- Children’s training should be matched to their biological development and movement skills rather than their chronological age alone.
- Early childhood should focus on play, enjoyment, and the development of fundamental movement skills, not competition or specialization.
- During late childhood, broad athletic development—including coordination, agility, speed, and participation in multiple sports—provides a stronger long-term foundation than early single-sport specialization.
- Progressive resistance training can be introduced safely in children and adolescents when it is age-appropriate, supervised, and focused on technique rather than maximal loading.
- The adolescent growth spurt (PHV) is a period of rapid physical change that requires careful management of training load and monitoring for growth-related overuse injuries.
- Research suggests that athletes who participate in multiple sports during childhood and specialize later are more likely to achieve long-term elite performance than those who specialize very early.
- Parents should support their child’s long-term development and enjoyment of physical activity rather than focusing primarily on early competitive success.
- The ultimate goal of youth sport is not simply to develop better young athletes, but to help children become healthy, physically literate, confident, and active adults.
Introduction: What Should Kids Train at Each Age
Walk into any youth sports club on a Saturday morning, and you’ll find eight-year-olds running specialized drills, ten-year-olds competing in single-sport tournaments year-round, and parents wondering whether their child is falling behind. The anxiety is understandable. Many parents invest enormous amounts of time, energy, and money into their children’s sports, hoping that early dedication and specialization will give them the best possible chance of success.
As a physician, coach, and father of seven children, I understand that motivation. Every parent wants to give their child the best possible opportunities. But through both my clinical work and years of coaching, I have also seen the other side of the equation. In some cases, training becomes too specialized, too intensive, or too repetitive before a child is developmentally ready. Rather than building a broad athletic foundation, some young athletes spend years practicing only one sport or one narrow movement pattern. This may increase the risk of overuse injuries and may also limit the development of the fundamental movement skills that underpin long-term athletic performance.
I also see the consequences later in life. As a coach, I occasionally work with adults and older teenagers who are beginning a new sport. It is often apparent when fundamental movement skills were never fully developed during childhood, either because physical activity was limited or because training was highly specialized from an early age. These athletes can still make excellent progress, but developing coordination, balance, agility, and movement efficiency is often more challenging than it would have been during childhood.
The reality is that only a small proportion of children will eventually become elite athletes, regardless of talent, motivation, or parental investment. For most children, the greatest value of sport lies elsewhere: building physical literacy, developing healthy habits, enjoying movement, and creating a foundation that supports lifelong health and physical activity. Ironically, these same principles also appear to give the minority who do pursue elite sport the best chance of reaching their potential.
Research in pediatric sports medicine and youth athletic development offers age- and maturation-informed principles that help coaches and parents make better training decisions. Knowing what children should train at each stage of development—and when—is one of the most valuable tools a parent or coach can have.
In this article, I review what the current scientific evidence says about training priorities at each developmental stage—from the movement foundations of early childhood to the performance optimization of adolescence—and explain how parents and coaches can help children build skills that benefit them not only in sport, but throughout life.
What Should Kids Train at Each Age: The Core Principles
Children are not simply small adults. Their nervous systems, musculoskeletal structures, hormonal environments, and psychological readiness evolve at distinct rates — and training that is optimal at age ten may be premature at age six and insufficient at age fourteen.
One influential framework for understanding what children should train at each age is the Long-Term Athletic Development (LTAD) model, which describes how training can be aligned with developmental age, physical literacy, and long-term participation in sport [7]. The model includes the concept of “windows of opportunity” — sensitive developmental periods in which children may be more responsive to specific training stimuli — although the evidence for the exact timing and rigidity of these windows remains debated [8]. For practical purposes, training progression should therefore be guided by biological maturity and individual readiness rather than calendar age alone.
A critical biological landmark in this process is Peak Height Velocity (PHV) — the period of fastest upward growth in stature, a hallmark of the pubertal growth spurt. PHV typically begins between 11.6–12.1 years for girls and 13.8–14.1 years for boys, with stature increasing at a mean rate of 10 cm per year (range 6–13 cm/year) for boys and 8 cm per year (range 5–11 cm/year) for girls during this window [1]. Both strength and power are significantly affected during the PHV period, and participation in sports training has been shown to mitigate these effects [1].
This is one reason why I often explain to young athletes and their parents that certain athletic qualities are best developed at certain stages of childhood and adolescence. If broad movement skills, coordination, balance, and basic athletic competence are neglected early, they can still improve later — but the process may be slower and more difficult.
This is also how we have tried to approach sport with my own children. Rather than pushing early specialization, we have prioritized varied activities from a young age, especially sports and exercises that develop fundamental movement skills. Specialization, if it happens, should come later on top of that broad foundation — not instead of it.
Stage 1: Active Start (Ages 0–6)
The foundational principle of early childhood physical development is simple: movement itself is the training. The critical period for fundamental movement skill (FMS) development occurs between 3 and 6 years of age [2]. These skills — running, jumping, hopping, throwing, catching, balancing — are the building blocks of all future athletic performance and physical literacy.
This is not yet a stage for structured sport. It is a stage for play — unstructured, varied, and joyful. The nervous system is undergoing rapid maturation, and diverse movement experiences are the most effective stimulus available.
What the evidence says: By the age of 6 to 8 years, the majority of children have the potential to achieve proficiency in fundamental movement skills. Poor FMS development in early life may be associated with difficulties in developing the physical fitness necessary for participation in various activities later in life [2]. Effective FMS acquisition requires collaborative support from teachers, parents, sports professionals, and healthcare providers [2].
What to prioritize:
At this stage, I usually recommend either a very simple sport or general physical activity that focuses on basic movement rather than performance. It does not even need to be a formal sport. Simple gymnastics, playful movement sessions, light ball games, climbing, swimming, rhythm-based activities, and varied outdoor play can all work well.
The key is variety. Children should move in different environments, use different objects, and experience different movement challenges: parks, playgrounds, grass, sand, water, music, rhythm, climbing structures, and balls. The themes and exercises should change often, so the child develops coordination, balance, spatial awareness, and confidence in their own body.
Prioritize free, unstructured active play, varied movement environments, and activities that feel enjoyable. At this stage, there is no need for specialization, sport-specific drills, or performance pressure.
Stage 2: FUNdamentals (Ages 6–9 Boys, 6–8 Girls)
This stage introduces structured physical activity while still emphasizing enjoyable and varied movement. Long-term athletic development models support a structured approach to youth training and emphasize the development of physical literacy, movement competency, coordination, and general physical fitness from an early age [9].
Multi-sport participation is generally recommended at this stage, rather than early single-sport specialization [10]. Activities should be varied across different movement patterns. Examples include running sports, throwing sports, racket sports, gymnastics, swimming, and martial arts, all of which can expose children to different but complementary movement challenges.
What the evidence says: The safety and efficacy of youth strength and conditioning programs depend on proper instruction, coaching, and supervision [3]. For this age group, bodyweight strengthening, agility, and cardiovascular exercise — preceded by dynamic warm-ups — are appropriate and evidence-supported modalities when delivered with proper instruction and supervision [3]. The emphasis at this stage should remain on movement quality and enjoyment.
What to prioritize:
At this stage, I usually recommend starting with one sport, several sports, or any form of physical activity that the child genuinely enjoys. The goal is not to decide whether this will become a lifelong sport, but to help the child experience success, enjoy movement, and simply get used to being physically active.
A sport at this age does not need to be “the right sport.” It can function as a bridge to future physical activity. The main priority is that the child moves, plays, tries different skills, and explores what their body can do in a positive and low-pressure environment.
Prioritize agility, balance, and coordination through games and varied sports; speed and reaction training through play-based activities; fundamental sport skills in a multi-sport context; creative movement, gymnastics-based exercises, dance, and rhythm activities; and simple bodyweight movements such as squatting, jumping, and landing.
At this stage, enjoyment matters more than performance. The child should leave training with a sense of success, curiosity, and confidence — not pressure to specialize too early.
Stage 3: Learn to Train (Ages 9–12 Boys, 8–11 Girls)
This is an important stage for developing broad athletic skills. Before early single-sport specialization becomes appropriate, training should emphasize coordination, balance, movement control, confidence, and exposure to different movement patterns. Current clinical recommendations encourage multisport participation in childhood and adolescence, especially for athletes under the age of 14. These recommendations also emphasize that youth sport should focus on the athlete’s individual needs rather than competitive outcomes [10].
The focus at this stage is on skill breadth, not depth. The goal is to develop a wide repertoire of movement skills across multiple sports — not to excel at one. Research comparing adult elite performance with childhood training history consistently shows that long-term adult-age success is associated with extensive childhood and adolescent multi-sport practice, a relatively late start in the main sport, and gradual initial progress [4]. Athletes who specialize early may perform well at junior level but may be less likely to reach adult world-class performance in many sports.
This stage is also an appropriate time to introduce structured physical conditioning, provided the emphasis remains on proper instruction, coaching, and supervision. Long-term athletic development models include the concept of developmental “windows of opportunity,” but the evidence base for the exact timing of these windows is limited and should not be interpreted rigidly [8]. Appropriate youth strength and conditioning modalities include bodyweight strengthening, resistance bands, agility, plyometrics, and cardiovascular exercise [3].
A note on early specialization: Adolescent sport specialization is associated with greater levels of burnout across all three dimensions — reduced sense of accomplishment, sport devaluation, and exhaustion — compared with sport sampling [5].
What to prioritize:
In my experience as a physician and coach, this is often the age when training demands begin to increase noticeably. Boys may be taken several times per week to football practices, tournaments, or academy-style programs, while girls may enter highly structured gymnastics, figure skating, or dance environments. In many families, the commitment becomes serious at this stage, and weekly training volume can increase rapidly.
This is not automatically a problem. Structured sport can be highly beneficial when the child enjoys it and the training remains well balanced. The concern is when training becomes too intensive, too repetitive, or too specialized before a broad athletic foundation has been established. This is also the age when I begin to see some children develop early overuse injuries, recurring aches and pains, or gradually lose the enjoyment of sport.
Even if the long-term goal is to specialize in a single sport, I generally encourage children at this stage to continue participating in two or more different sports whenever practical. The available evidence suggests that maintaining variety during late childhood may provide broader motor development and may be more beneficial for long-term athletic development than specializing too early.
Training should focus on continued multi-sport participation, technical skill development across different movement contexts, speed and agility through both general and sport-specific activities, structured dynamic warm-ups, and the gradual introduction of basic resistance training using bodyweight and light external resistance under appropriate supervision.
Stage 4: Train to Train (Ages 12–16 Boys, 11–15 Girls)
The onset of PHV changes the training environment. During the adolescent growth spurt, the body is changing rapidly, coordination may temporarily fluctuate, and growth-related overuse injuries become an important consideration. Rapid increases in stature and lower-limb length have been associated with greater injury incidence and burden in youth athletes, and growth-related injuries appear to cluster around the adolescent growth spurt [11].
For this reason, coaches should be cautious about rapidly increasing training volume or intensity during this period. The priority should be to maintain technique, physical literacy, progressive loading, and adequate recovery, while monitoring for symptoms such as persistent anterior knee pain, heel pain, growth-plate irritation, Osgood-Schlatter disease, Sever’s disease, tendinopathy, and other overuse problems.
Progressive resistance training is appropriate for young athletes when it is based on proper instruction, coaching, and supervision. Age-appropriate strength and conditioning should aim to improve movement skills and promote long-term athletic development [3].
Early specialization risk at this stage: Early sport specialization is often defined as engaging in more than 8 months of a single sport before the age of 14 years, and research has suggested that it is associated with increased risk of injury in various sports, for both boys and girls, as well as burnout and sport dropout [6]. Clinicians and coaches are encouraged to support multisport participation through early adolescence.
In my experience as both a physician and a coach, this stage is often where youth sport changes dramatically. Training becomes more structured, competition becomes more important, and weekly training volumes often increase. At the same time, puberty brings major physical and psychological changes, and many young athletes begin to develop new interests outside sport.
This is also the age when I frequently see children either change sports or stop participating altogether. Unfortunately, some never replace their original sport with another form of physical activity and gradually become inactive. For that reason, parents should continue to stay engaged during this period — not by increasing pressure to perform, but by helping their child maintain an enjoyable and sustainable relationship with physical activity.
From a training perspective, the focus should shift gradually toward more structured conditioning while still preserving variety. Aerobic base development can be combined with sport-specific conditioning, while speed and power training can be introduced progressively as physical maturation advances. Progressive resistance training is also appropriate when technique, supervision, and load progression are handled properly [3].
At the same time, this is not a stage where all other physical activities should automatically disappear. Even if the athlete begins to focus more seriously on one sport, gradual narrowing from multiple sports to one or two preferred sports is usually a better approach than complete exclusion of other movement experiences. Core stability, injury-prevention work, and careful monitoring of growth-related overuse symptoms become especially important during this period, particularly in female athletes approaching PHV.
If a young athlete repeatedly complains of pain in the same area, it should not automatically be dismissed as “normal growing pain.” During this stage, recurrent or persistent pain may reflect excessive training load, inadequate recovery, or growth-related overuse conditions such as Osgood-Schlatter disease, Sever’s disease, growth plate irritation, tendinopathy, or other overuse problems.
Stage 5: Train to Compete (Ages 16+ Boys, 15+ Girls)
By late adolescence, many athletes have moved beyond the most disruptive phase of the adolescent growth spurt, and increasing neuromuscular maturity allows training to become more structured, progressive, and competition-focused [12]. This supports the use of more structured and progressive training, while sport specialization should still be built on a broad athletic foundation rather than years of narrow, repetitive loading.
Athletes who arrive at this stage with a background in varied sport participation may have a stronger foundation for later sport-specific development than athletes whose early development has been dominated by a single sport. This is consistent with research showing that, compared with national-class athletes, adult world-class athletes had more childhood and adolescent multi-sport coach-led practice, a later start in their main sport, less main-sport practice, and slower initial progress [4].
What to prioritize:
By this stage, training often begins to resemble adult sport. In many disciplines, such as combat sports, adolescents gradually transition into adult training groups, where they are exposed to more experienced athletes and higher performance expectations. In my experience as a coach, this is often an important turning point. Young athletes begin to take greater responsibility for their own training, learn by observing older athletes, and shift their focus from simply participating to pursuing long-term improvement.
Training priorities now become increasingly sport-specific. Progressive strength and power training can be integrated within a periodized program, technical and tactical skills become more refined, and sport-specific conditioning takes on a larger role. Nutrition, recovery, and sleep also become increasingly important, as they directly influence both performance and the ability to tolerate higher training loads. Structured competition and regular performance monitoring can help guide long-term progression while reducing the risk of excessive training or stagnation.
The One Question Every Parent Should Ask
The most valuable question a parent or coach can ask at any age is not “Is my child good enough?” but rather “Does my child move well, enjoy movement, and want to keep moving?”
Parents should also be willing to examine their own motivations. It is natural to want the best for your child, and it is understandable to feel proud when they succeed. But in youth sport, the line between supporting a child and projecting adult ambitions onto them can sometimes become blurred. Some parents may begin to identify strongly with their child’s athletic progress, hoping to experience success through the child’s achievements.
In my view, this is not the best foundation for guiding a young athlete. The central question should always be what genuinely serves the child’s long-term wellbeing, development, and relationship with sport — not what satisfies the parent’s expectations, identity, or unfinished ambitions.
Available evidence suggests that long-term adult-age success is associated with extensive childhood and adolescent multi-sport practice, a relatively late start in the main sport, gradual initial progress, and only moderate childhood and adolescent specialized main-sport practice [4]. This supports a youth development approach that prioritizes early diversification before later specialization.
Conclusion: What Should Kids Train at Each Age and Why It Matters
Age-appropriate athletic development is not about holding children back. It is about building them forward. What children should train at each age depends less on how early they can compete and more on whether the training matches their biological maturity, movement skills, motivation, and long-term wellbeing.
In early childhood, the priority is play, movement exploration, and fundamental movement skills. In later childhood, the focus should shift toward broad athletic competence, multi-sport participation, coordination, speed, agility, and basic strength. During puberty and the adolescent growth spurt, training can become more structured, but load, recovery, injury risk, and psychological readiness must be monitored carefully. By late adolescence, progressive specialization and more adult-like training can make sense — but ideally on top of a broad physical foundation rather than years of narrow, repetitive loading.
For parents, the most important point is this: youth sport should not be judged only by medals, rankings, or early performance. A child who moves well, enjoys training, stays healthy, and wants to keep participating is already developing something valuable. For the small minority who later pursue elite sport, this broad foundation may also improve their long-term chances. For everyone else, it builds physical literacy, confidence, health, and a lifelong relationship with movement.
The best youth training plan is not the one that tries to create the best 10-year-old athlete. It is the one that helps the child become a healthy, capable, motivated, and physically confident adult.
References
[1] https://doi.org/10.3390/jfmk10020168
[2] https://www.mdpi.com/2227-9067/12/10/1406
[3] https://pubmed.ncbi.nlm.nih.gov/39108442/
[4] https://pubmed.ncbi.nlm.nih.gov/35038142/
[5] https://pubmed.ncbi.nlm.nih.gov/32166094/
[6] https://pmc.ncbi.nlm.nih.gov/articles/PMC11299332/
[7] https://www.ebsco.com/research-starters/sports-and-leisure/long-term-athlete-development-ltad
[8] https://pubmed.ncbi.nlm.nih.gov/21259156/
[9] https://pubmed.ncbi.nlm.nih.gov/25486295/
[10] https://journals.sagepub.com/doi/10.1177/15563316241237526
