Abstract
Youth sports participation has become increasingly professionalized, with children training at volumes and intensities once reserved for adult elite athletes and specializing in a single sport earlier than in previous generations. This paper reviews the physical, psychological, and developmental harms associated with overtraining in young children, drawing on current clinical guidance from the American Academy of Pediatrics and the National Athletic Trainers' Association alongside peer reviewed literature. The review finds well documented physical harm, most notably overuse and growth plate, or physeal, injury, a category of injury essentially exclusive to a still growing skeleton, as well as broader overtraining syndrome affecting endocrine, neurologic, and cardiovascular function. It finds well documented psychological harm, including burnout, impaired well being, decreased quality of life, and sport dropout, associated with excessive training volume and early single sport specialization. It also finds evidence of endocrine and psychological harm through Relative Energy Deficiency in Sport, though this evidence is most robustly established in adolescent athletes rather than in preadolescent children specifically, a distinction the review treats as important rather than incidental. Major pediatric and sports medicine organizations converge on similar recommendations: limiting early single sport specialization, ensuring adequate recovery relative to growth stage, and prioritizing participation and enjoyment over intensive early competition. This paper is a narrative synthesis intended for general informational purposes and is not a substitute for individualized pediatric medical or sports medicine guidance.
Introduction
Youth sports participation has grown increasingly professionalized over the past two decades, with children training at volumes and intensities once reserved for adult elite athletes and specializing in a single sport at younger ages than in previous generations. This shift is often driven by a belief, among parents, coaches, and young athletes themselves, that more training and earlier specialization improve long term athletic outcomes and competitive opportunity.
Pediatric sports medicine literature describes physiologic vulnerabilities specific to children that make this population differently, and not merely more mildly, susceptible to high training loads than adult athletes. A child's growth plates, the areas of developing cartilage near the ends of long bones, are weaker than fully mature bone, tendon, or ligament, which creates categories of overuse injury that simply do not exist in an adult skeleton. Evidence on the physical, psychological, and developmental consequences of overtraining and early specialization in youth athletes has accumulated substantially, culminating in updated clinical guidance from major pediatric and sports medicine organizations, including an updated American Academy of Pediatrics clinical report published in 2023.
This paper reviews the physical, psychological, and developmental harms associated with overtraining in young children as described in current pediatric sports medicine and sports psychology literature, and asks three questions. First, what specific physical harms are attributable to overtraining in a still growing body, as distinct from the overtraining risks documented in adult athletes. Second, what psychological and developmental harms accompany excessive training volume and early sport specialization. Third, what do major pediatric and sports medicine organizations currently recommend to reduce this risk, and how consistent is that guidance across organizations. The paper is organized as a narrative review grounded in current clinical guidance and peer reviewed literature rather than a systematic review, a meta analysis, or new primary research.
Methodology
Review design and scope
This paper uses a narrative review methodology rather than a systematic review, a meta analysis, or a primary study involving human participants. Its scope is the physical, psychological, and developmental harms associated with overtraining specifically in young, still growing children, though as detailed below, some of the literature reviewed is more robustly established in adolescent athletes than in preadolescent children, a distinction this review makes explicit rather than treating the two populations as interchangeable.
Source selection and the search performed for this section
Following the search step this skill requires for Methodology, three gaps were identified before drafting: current clinical guidance on overuse injury, overtraining, and burnout in young athletes; the specific mechanism and population most associated with growth plate, or physeal, injury; and current evidence on Relative Energy Deficiency in Sport as a psychological and endocrine harm pathway. All three were closed with a web search prioritizing clinical guidance from professional pediatric and sports medicine organizations and peer reviewed literature over patient facing summaries.
The search confirmed that the American Academy of Pediatrics published an updated clinical report, "Overuse Injuries, Overtraining, and Burnout in Young Athletes," in the February 2023 issue of Pediatrics, building on an earlier 2016 clinical report on sports specialization and intensive training. The National Athletic Trainers' Association maintains a position statement on the prevention of pediatric overuse injuries. A 2025 scoping review examined the relationship between overtraining and injury rates specifically in school age athletes. These sources describe extended training loads that exceed recovery capacity as capable of producing overtraining syndrome, with decreased performance and derangement of endocrine, neurologic, cardiovascular, and psychological systems, and describe physeal injuries, injuries to the growth plate, as a category of overuse injury exclusive to pediatric populations, since growth plates are weaker than mature bone, tendon, or ligament. Commonly cited examples affecting the knee, Osgood-Schlatter disease and Sinding-Larsen-Johansson syndrome, are described as most common in athletes around 12 to 13 years old in running and jumping sports such as soccer, basketball, and volleyball.
The search for Relative Energy Deficiency in Sport found that this condition, arising when energy intake is insufficient relative to training demand, is associated with compromised bone health, endocrine disruption, cardiovascular and gastrointestinal dysfunction, and psychological effects including mood disturbance, anxiety, irritability, and disordered eating risk, with athletes exhibiting perfectionist traits at particularly elevated risk of burnout, anxiety, depression, and, in severe cases, suicide. The material reviewed here describes this evidence base as most extensively developed in adolescent athletes, frequently female adolescent athletes in sports emphasizing low body weight or appearance, rather than in preadolescent children specifically.
Analytic categories
Three terms recur throughout the Results and Discussion and are defined here for consistency. Physical harm refers to a documented injury or physiologic derangement, overuse injury, physeal injury, or systemic overtraining syndrome. Psychological and developmental harm refers to documented effects on mood, motivation, well being, sport participation, or long term psychosocial development. Age specificity refers to whether the population a given source actually studied was preadolescent children, adolescents, or youth athletes described broadly without that distinction, since this review treats that distinction as materially important rather than assuming uniform applicability across all ages under eighteen.
Sources consulted
- Primary: Overuse Injuries, Overtraining, and Burnout in Young Athletes (American Academy of Pediatrics clinical report, Pediatrics, 2023)
- Primary: Sports Specialization and Intensive Training in Young Athletes (American Academy of Pediatrics clinical report, Pediatrics, 2016)
- Primary: National Athletic Trainers' Association position statement on prevention of pediatric overuse injuries
- Primary: The Impact of Overtraining on Injury Rates in School Age Athletes, a scoping review (PMC)
- Primary: Relative Energy Deficiency in Sport (RED-S) in Adolescents, a practical review (PubMed)
- Secondary, used only for general context, not as the basis for a specific claim: Preventing Youth Sports Injuries (Cedars-Sinai)
- Secondary: Relative Energy Deficiency in Sport (Boston Children's Hospital)
Limitations of this methodology
This review is a narrative synthesis, not a systematic review or a meta analysis, and does not independently verify effect sizes or injury incidence figures beyond what the cited clinical reports and peer reviewed sources report themselves. It relies partly on secondary, patient facing sources for general context alongside the primary clinical reports and position statements that anchor its specific claims. The age specificity of the underlying literature is not uniform across the harms reviewed, physeal injury evidence concentrates in preadolescent and early adolescent children, while Relative Energy Deficiency in Sport evidence concentrates in adolescents, which limits how confidently any single claim in this paper can be generalized across the full range of ages the title's phrase "young children" might suggest.
Results
The review produced findings across three domains, summarized below.
| Domain | Documented harm | Population most supported by the evidence reviewed |
|---|---|---|
| Physical: overuse and growth plate injury | Growth plates are weaker than mature bone, tendon, or ligament, making physeal injury, for example Osgood-Schlatter disease and Sinding-Larsen-Johansson syndrome, a category of overuse injury exclusive to a still growing skeleton | Preadolescent and early adolescent children, commonly cited around 12 to 13 years old for the knee conditions named |
| Physical: general overtraining syndrome | Training loads exceeding recovery capacity can produce overtraining syndrome, with decreased performance and derangement of endocrine, neurologic, cardiovascular, and psychological systems | Youth athletes broadly, without strong age differentiation in the sources reviewed |
| Physical and endocrine: Relative Energy Deficiency in Sport | Low energy availability relative to training demand is associated with compromised bone health, endocrine disruption, and cardiovascular and gastrointestinal dysfunction | Most robustly established in adolescent athletes, particularly in sports emphasizing low body weight or appearance; less established specifically in preadolescent children |
| Psychological and developmental: burnout and dropout | Excessive training volume, scheduling pressure, and early single sport specialization are associated with burnout, impaired well being, decreased quality of life, and sport dropout | Youth athletes broadly, per American Academy of Pediatrics guidance |
| Psychological: mood and eating related effects | Relative Energy Deficiency in Sport is specifically associated with mood disturbance, anxiety, irritability, and disordered eating risk, more severe in athletes with perfectionist traits | Most robustly established in adolescent athletes |
Two cross cutting findings stand out. First, growth plate, or physeal, injury is the one harm category genuinely exclusive to a still growing skeleton, and distinguishes childhood overtraining risk qualitatively, not merely by degree, from overtraining risk in adult athletes. Second, the evidence base is not uniform across ages: physeal injury is best documented in preadolescent and early adolescent children specifically, while Relative Energy Deficiency in Sport and some psychological literature is most robustly established in adolescents, meaning a claim well supported for one age band should not be assumed to transfer directly to the other without its own evidence.
Discussion
The review confirms multiple, well documented categories of harm associated with overtraining in young athletes: physical harm through overuse and growth plate injury and through broader overtraining syndrome, psychological and developmental harm through burnout, impaired well being, and sport dropout, and combined physical and psychological harm through Relative Energy Deficiency in Sport. This gives the paper's own title solid support in a broad sense. The review also finds, however, that this support is not uniform across the population the title's phrase "young children" might be read to cover. Physeal injury risk is described specifically in preadolescent and early adolescent children, while Relative Energy Deficiency in Sport and related psychological evidence is most robustly established in adolescents rather than in younger children specifically. A reader should treat the title's claim as strongly supported for physical, overuse related harm across the full childhood age range, and as most strongly supported for the endocrine and eating related psychological harm specifically in adolescents, rather than assuming identical evidentiary strength across every age band at once.
The organizations reviewed here converge on similar practical guidance despite covering somewhat different evidence bases: the American Academy of Pediatrics and the National Athletic Trainers' Association both point toward limiting early single sport specialization, ensuring recovery adequate to a child's growth stage, and prioritizing participation and enjoyment over intensive early competition, rather than a single training load threshold that applies uniformly to every child. This convergence across independently issued guidance strengthens confidence in the general direction of the recommendation even where the underlying evidence for a specific mechanism, such as Relative Energy Deficiency in Sport, is still concentrated in a narrower age band.
This paper is a narrative synthesis intended for general informational purposes. It is not a substitute for individualized pediatric medical or sports medicine guidance, and a parent, coach, or clinician with a concern about a specific child's training load, symptoms, or well being should consult a qualified pediatric sports medicine professional rather than rely on this review alone.
Limitations
This review is a narrative synthesis rather than a systematic review or a meta analysis, and it did not independently verify injury incidence figures or effect sizes beyond what the cited clinical reports and peer reviewed sources themselves report. It relies in part on secondary, patient facing sources for general context alongside the primary clinical guidance and peer reviewed literature that anchor its specific claims. Most significantly, the age specificity of the underlying evidence is uneven: physeal injury evidence concentrates in preadolescent and early adolescent children, while Relative Energy Deficiency in Sport evidence concentrates in adolescents, which limits how confidently any single finding in this paper generalizes across the full age range the topic implies. Future work would benefit from research that examines all three harm domains, physical, psychological, and endocrine, specifically within a preadolescent population, rather than relying on evidence developed primarily in adolescent athletes for the psychological and endocrine domains.
Conclusion
Overtraining in young children is associated with well documented physical harm, most notably growth plate, or physeal, injury, a category exclusive to a still growing skeleton, alongside broader overtraining syndrome affecting endocrine, neurologic, and cardiovascular function, and with well documented psychological and developmental harm, including burnout, impaired well being, and sport dropout, per current guidance from the American Academy of Pediatrics and the National Athletic Trainers' Association. The strength of this evidence is not uniform across age or harm type: physical, overuse related harm is well supported across the childhood age range, while Relative Energy Deficiency in Sport and related psychological and endocrine harm is most robustly established specifically in adolescents. Organizations reviewed here converge on similar mitigating guidance regardless of that evidentiary difference: limiting early single sport specialization, ensuring recovery matched to growth stage, and prioritizing participation and enjoyment over intensive early competition. This paper is informational and does not substitute for individualized pediatric medical or sports medicine advice. The primary gap remaining for future work is research examining physical, psychological, and endocrine harm together within a preadolescent population specifically, rather than extending evidence developed primarily in adolescents to younger children by assumption.