sports specialization final
TRANSCRIPT
Nicole R. Miela
NATA # 66087
677 Fairledge
Lake Orion, MI 48362
(586) 484-3448
Saginaw Valley State University
Junior
The Effects of Early Sports Specialization on Youth and Adolescent Athletes:
A Systematic Review
Literature Review: Methodological
Nicole R. Miela
677 Fairledge
Lake Orion, MI 48362
(586) 484-3448
Saginaw Valley State University
David C. Berry, PhD, AT, ATC, ATRIC, CKTP, GT Certified
Department of Kinesiology
College of Health and Human Services, Rm H212
Saginaw Valley State University
7400 Bay Road
University Center, MI 48710
989-964-4504 (O)
989-964-4925 (F)
The Effects of Early Sports Specialization on Youth and Adolescent Athletes:
A Systematic Review
The Effects of Early Sports Specialization on Youth and Adolescent Athletes: A
Systematic Review
Context: Early sports specialization can be detrimental to a young athlete’s well-being,
and it is recommended that sports diversification, or participation in different sports be
practiced until after puberty. Objective: Systematically review the literature to determine
how early sports specialization affects young athletes. Data Sources: Articles were
identified from multiple electronic database searches from January 1990-to-September
2014 using the terms: “child and child development and youth sports specialization or
sports specialization” and “adolescent and adolescent development and youth sports
specialization or sports specialization,” resulting in 16 studies. Study Selection:
Inclusion criteria included: (1) peer-reviewed level 1-5 research/reports/abstracts
following Oxford’s Centre for Evidence-Based Medicine, (2) English language, (3)
available abstract, (4) children/adolescents ages 4-20, and (5) outcomes or
expert/association recommendations effected by early sports specialization. Data
Extraction: Two reviewers independently assessed studies using the Strengthening in
the Reporting of Observational Studies in Epidemiology (STROBE) checklist when
applicable. Data of interest included: subjects; descriptive, univariate, and/or
multivariate data, odds ratios (OR) and relative risk (RR), and expert/association
recommendations. Data Synthesis: Eight articles met the inclusion criteria, 3-level-2b,
1-level-4, 4-level-5. Specialized injured athletes were older than those uninjured
(p<.001) and played organized sport more hours/week (p<.001). Specialization was an
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independent risk factor for injury after other variable adjustment (OR=1.48, p<.05).
Specialization in females increased the risk of patellofemoral pain (RR=1.5, p=.038) and
Sinding-Larsen-Johannson/patellar-tendinopathy/Osgood-Schlatter-disease (RR=4,
95%, p=.005). Consistent expert/association recommendations include: (1) monitoring
training and fatigue levels, (2) assigning 1-2 days of absolute rest per-week, and (3)
delaying specialization until late adolescence. Conclusions: Early sports specialization
contributes to increased risk of overuse injuries in young athletes and contributes to
greater rates of attrition from activity in young adulthood. Training and rest should be
balanced to diminish incidence of fatigue, and specialization should be delayed to
decrease sport attrition.
Key Words: specialization, youth, adolescent
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INTRODUCTION
Sports specialization has recently been defined as the intense training in one
particular sport with the exclusion of other sports.1 This phenomenon naturally occurs as
young athletes mature and discover in which sport his or her passion lies. Oftentimes,
what type of sport an athlete specializes in dictates at what age specialization should
occur in order to be successful in their chosen sport. Individualized sports such as
swimming, figure skating, or gymnastics require the athlete to begin intense training at a
younger age; however, high level training at such a young age can also hinder social
development.2
Athletes in team-based sports like baseball, soccer, or basketball benefit from
diversification, or participating in a wide variety of sports, at a younger age. The
National Athletic Trainers’ Association details how such diversification can limit chronic
overuse injuries and promotes better general well-being of the athlete.3 Specialization
has also been associated with burnout and eventual dropout from that sport, meaning
athletes tend to grow tired and frustrated with the single sport they are playing and
ultimately stop playing if they specialized at a younger age compared to their diversified
peers.4 Despite the benefits in some sports for delayed specialization, parents, coaches,
and perhaps even the athletes themselves are encouraging early specialization for the
draw of college scholarships and success garnering up to the Olympic and professional
level.
Malina5 describes how often this causes the athlete to play year-round in a single
sport to gain such success. Often times, the leagues these young athletes play in are
modeled after adult leagues, encouraging a competitive, “win-at-all-costs” atmosphere
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that may be detrimental to the young athlete’s health and safety.6 The American
Academy of Pediatrics’ Committee on Sports Medicine and Fitness agree that multisport
athletes that specialized in a sport after puberty tend to perform in their sport more
consistently, participate in the sport longer, and have fewer injuries than those athletes
who specialized sooner.7
The majority of the literature that currently exists relative to early sport
specialization is based upon expert opinion and recommendations; however, the body
of evidence supporting late specialization and combating early specialization is growing
to include observational, retrospective, and prospective studies. Therefore, we set out to
systematically review the current literature to determine how sport specialization affects
the development of youth and adolescent athletes.
METHODS
Data Sources
Relevant articles were identified through PubMed, MEDLINE, the Cumulative
Index to Nursing and Allied Health Literature (CINAHL), and the Physical Therapy &
Sports Medicine Collection from January 1990 to September 2014 using the following
terms: “child and child development and youth sports specialization or sports
specialization” and “adolescent and adolescent developments and youth sports
specialization or sports specialization.” Included studies were peer-reviewed academic
journal articles published between January 1990 and September 2014 written in English
that contained study outcomes or recommendations for youth and adolescent athletes
and sports specialization.
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Study Selection
Studies identified in our search included study outcomes or expert
recommendations that were effected as the result of early sports specialization. Due to
the majority of the literature consisting of expert recommendations, all peer-reviewed
level 1-5 evidence following Oxford’s Centre for Evidence-Based Medicine (CEBM)8
grading scale with an available abstract were eligible for inclusion. Sixteen articles were
selected and read for inclusion. A total of eight articles met the inclusion criteria, three
level 2b, one level 4, and four level 5, To be considered for inclusion, the following
criteria were used: (1) peer-reviewed level 1-5 research/reports/abstracts following
Oxford’s Centre for Evidence-Based Medicine (CEBM),8 (2) written in English, (3)
available abstract, (4) involved children and adolescents ages 4-20, and (5) included
study outcomes or expert/association recommendations effected by early sports
specialization. Figure 1 outlines the study selection process.
Data Extraction
Two reviewers independently assessed the included studies and expert
recommendations according to the Strengthening in the Reporting of Observational
Studies in Epidemiology (STROBE)9 checklist and the Oxford Centre for Evidence-
Based Medicine (CEBM)8 level of evidence classification system. All expert/association
recommendation articles were automatically graded level 5 evidence according to
CEBM classification. The reviewers came together to discuss and compare their
independent STROBE assessments of the four empirical studies and impressions of the
four expert recommendation articles. Data of interest included: (1) subjects; (2) methods
of observation; (3) descriptive (e.g., means, SD), univariate, and/or multivariate data, (4)
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odds ratios (OR), relative risk (RR), and 95% confidence intervals (CI); and (5)
frequency of similar recommendations.
RESULTS
Four original research articles and four expert/association recommendation
articles were included in the final review. Summaries of data from the research articles
are presented in Table 1. Summaries of expert/association recommendation articles are
presented in Table 2.
Jayanthi et al10 have reported baseline values from an ongoing 3-year
prospective case-control study. In order to determine how sports specialization, training
volume, and growth rate are associated with increased risk for injury in young athletes,
injured athletes between the ages of 7 and 18 presenting to sports medicine clinics and
healthy controls presenting for sports physicals at primary care clinics were recruited.
The 1,206 participants were assessed for how many hours per week were spent in
organized sports, free play, and gym as well as sports specialization and growth rate
information. These independent variables were then used to determine relationships to
the dependent variables of total injuries, acute injuries, overuse injuries, and serious
overuse injuries.
Injured athletes were reported to be older than uninjured athletes (14.1±2.1 vs.
12.9±2.6 years, p<.001) and played on average more hours per week in organized
sports (11.3±6.9 vs. 9.4±8.2 hours, p<.001). After adjusting for hours per week in total
activity and age, sports specialization remained an independent risk factor for injury (OR
1.48, p<.05). Athletes who spent more hours per week in sport than they were old
(p<.05) and spent more than two times more participation in organized sport than free
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play (p=.001) were more likely to sustain a serious overuse injury. Growth rates
appeared to have no impact on injury status (4.76 vs. 4.79 cm/yr, p-value not reported).
A retrospective cohort epidemiology study by Hall et al11 examined the
relationship of sport specialization and increased anterior knee pain in female
adolescent athletes. A total of 546 athletes diagnosed with patellofemoral pain were
recruited from basketball, soccer, and volleyball programs in a public school district in
Kentucky. Of these athletes, 357 played multiple sports and 189 played a single sport.
Of those that played one sport, 66 played basketball, 57 played soccer, and 66 played
volleyball. Initial testing utilized the Anterior Knee Pain Scale (AKPS),12 International
Knee Documentation Committee (IKDC)13 form, a standardized history and physician-
administered musculoskeletal examination, and a medical history. Self-reported
maturational estimates for menses status, breast development, and hair growth as well
as anthropometric data consisting of height, weight, fat percentage, and body mass
index (BMI) were later taken to examine between group differences.
In order to normalize and best estimate exposure data, each sport was assigned
equal weight and was equivalent to one season of exposure. Group differences in
height, mass, and age was evaluated through a one-way ANOVA and significance was
set a priori at p<.05. Incidence rate ratios (IRR) and 95% confidence intervals (CI)
examined differences between specialized and multisport athletes. The relative risk of
patellofemoral pain increased 1.5 fold (95% CI 1.0-2.2, p=.038) in athletes who
specialized in a single sport. Single sport athletes also demonstrated a four-fold greater
relative risk for Sindig-Larsen-Johannson disease/ patellar tendinopathy (95% CI 1.5-
10.1, p=.005) and Osgood-Schlatter disease (95% CI 1.5-10.1, p=.005). Other anterior
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knee pain diagnoses such as fat pad, plica, pes anserine bursitis, and IT band
tendonitis showed no significant between group differences (p>.05). On average, single
sport athletes were older (14.5, 95% CI 14.3-14.7 years, p<.05), taller (162.4, 95% CI
161.3-163.5 cm, p<.05), and heavier (57.6, 95% CI 55.9-59.2 kg, p<.05) than multisport
athletes (13.8, 95% CI 13.6-14.0 years, p<.05; 160.2, 95% CI 159.4-161.1 cm, p<.05;
54.3, 95% CI 53.0-55.6 kg, p<.05).
Russell and Limle14 surveyed 153 university students, 71 male and 82 female,
between the ages of 18 and 22 in general education wellness courses. A demographic
questionnaire collected basic demographics, past and present sport and exercise
participation and specialization, and general retrospective perceptions of past youth
sport experience based on risks and benefits of participation and reasons for
participation and attrition. The Physical Activity Enjoyment Scale (PACES)15 was also
used to assess enjoyment of physical activity. Survey packets were administered
directly to participants and were completed in less than fifteen minutes. Independent t-
tests were performed to analyze if current enjoyment of physical activity was affected by
specialization status as well as if overall positive perceptions of past youth sport
experience differed due to specialization status. Chi-square tests and multiple
regression analyses were also performed to analyze the relationships among variables.
Significance was set a priori at p=.05 for all assessments.
Eighty-seven participants (56.9%) of the final sample of 153 reported practicing
youth sport specialization, most frequently in basketball (n=17), soccer (n=17), softball
(n=11), football (n=11), and baseball (n=10). When asked what age specialization
began, 17 participants (11.1%) specialized at age 8, and 15 participants (9.8%) reported
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specialization at age 5. Of all survey participants, 54 (35.3%) reported attrition from their
specialized sport. Independent t-tests were non-significant for specialization status’s
effect on physical activity enjoyment (t=.496, p>.05), frequency of current aerobic
exercise (t=.101, p>.05), frequency of current strength training (t=1.74, p>.05), and
overall retrospective perceptions of past youth sport participation (t=.310, p>.05). Chi-
square testing revealed a significant negative relationship between specialization and
current sport participation (χ2(2)=8.77, p<.05), suggesting that those who specialized in
a single sport compared to those who played multiple sports in youth were less likely to
participate in sports as young adults. From the multiple regression analysis, an overall
significant equation (F(3,149)=7.32, p<.001, R2=.128) showed that youth sport
experience perceptions were a better predictor than specialization status and gender in
predicting physical activity enjoyment as young adults.
Russell16 later surveyed 200 university students in general education wellness
courses, 93 male and 107 female, ranging in age from 17 to 22. Participants filled out a
demographic questionnaire to identify their background information, past and present
sports and exercise participation and specialization, and reasons for participation and
withdrawal as applicable. The Physical Activity Enjoyment Scale (PACES)15 and the
Sport Motivation Scale (SMS)17 were also utilized to measure enjoyment of physical
activity and the intrinsic motivation, extrinsic motivation, or amotivation to participate in
sports. Changes were made to the SMS to ensure items more applicable to the study’s
retrospective nature. Survey packets were administered directly to the participants and
were completed in less than ten minutes. Independent t-tests, chi-square analyses, and
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one-way MANOVAs were performed to analyze the relationships among variables.
Significance was set a priori at p=.05.
Over half (113 or 56%) of participants reported specializing as a youth in a single
sport, with basketball, softball, soccer, and football accounting for 73% of the
specialized sports. Of the 113 that reported specialization, 101 (89%) specialized before
adolescence, 72 (71%) specialized before the age of ten, and 21% specialized at the
age of six. Of all survey participants, 103 (51.5%) reported attrition from sport as young
adults. Specializers’ main reasons for attrition were (1) lack of time (n=17), (2) lost
interest (n=12), and (3) lack of fun (n=10); nonspecializers’ reported (1) lost interest
(n=10) and (2) lack of time (n=8). A MANOVA analysis revealed a significant effect for
specialization status on reported reasons young adults participated in youth sports
(Wilk’s λ=.872; F(9,190)=3.10, p<.05, η2p=.13). Follow-up ANOVAs revealed significant
reasons for specializers’ participation as to stay in shape (F(1,198)=5.08, p<.05,
η2p=.03), learn or improve skills (F(1,198)=10.20, p<.01, η2
p=.05), and to feel competent
about physical abilities (F(1,198)=10.49, p<.01, η2p=.05). A chi square test yielded a
significant relationship between youth specialization and current sport participation
(χ2(2)=6.43, p<.05) with specializers more likely to report attrition through young
adulthood (59%) than non-specializers (41%). MANOVA tests revealed a significant
effect of specialization on SMS scores (Wilk’s λ=.924; F(7,192)=2.27, p<.05, η2p=.08),
and follow-up ANOVAs showed specializers as higher on intrinsic motivation to know
(F(1,198)=4.83, p<.05, η2p=.03) and introjected extrinsic motivation (F(1,198)=4.18,
p<.05, η2p=.02) than non-specializers.
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Jayanthi et al1 examined original research articles, consensus opinions, and
position statements pertaining to sports specialization, expert athletes, or elite versus
novice athletes and made evidence-based recommendations based on their findings.
Included articles examined past diversification and/or specialization practices of elite,
near-elite, and sub-elite athletes in rhythmic gymnastics, field hockey, ice hockey,
tennis, wrestling, basketball, and other elite and Olympic sports and found that most
elite athletes, with the exception of gymnasts, did in fact practice early diversification
instead of specialization. Using the Strength of Recommendation Taxonomy (SORT),18
the authors made two level B clinical recommendations for intense single-sport
specialization. Based on their evidence, they found that early diversification is more
likely to lead to success in most the first recommendation maintains that while
specialization is necessary for skill development on the elite level in most sports, it
should be delayed until late adolescence to optimize success. The second
recommendation supports delayed specialization of most sports until late adolescence
as a means of reducing the risk for injury and negative psychological stress due to the
high risks and demands intense specialized training places on the young athlete.
The American Academy of Pediatrics Committee on Sports Medicine and
Fitness7 published a statement examining the potential risks of high levels of intense
training and specialization as a young athlete. Concerns over cardiac health, frequency
of musculoskeletal injury, musculoskeletal growth disturbances, proper nutritional
intake, sexual maturation in females, negative psychosocial consequences, and risk for
heat illness associated with early specialization led the committee to form six
recommendations (Figure 2) to assure safe and healthy sports participation at a time
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lacking appropriate and practical guidelines and research on the topic of early
specialization. These recommendations encourage children to participate in sports at
their own level, delay specialization until adolescence, take adequate rest periods from
sport to decrease risk of overuse injury, and meet the proper nutritional needs for the
child’s activity. Physicians, coaches, and parents are encouraged to recognize and
prevent overuse and heat related injuries and ensure the child is in a good sport
environment using the proper equipment and learning the correct techniques
appropriate for youth athletes. In addition, the child’s physician should monitor body
weight, cardiovascular health, sexual maturation, and signs and symptoms of
overtraining and emotional stress.
In an expert recommendation article, Johnson19 examined predisposing intrinsic
and extrinsic risk factors for overuse injuries and the relationship between overtraining
and specialization, especially when burnout has occurred. Stress is placed on the
benefits of a warm-up and how best to organize practices in order to reduce injury while
still enhancing performance. He recommended gradual progression of skills, random
practice, rest, age-appropriate activities, and monitoring athletes for signs of fatigue.
Additional recommendations included a change in activity every two to three months
and encouragement of diversification.
DiFiori20 recommended the use of pre-participation physical examinations to
gauge a young athlete’s cognitive, maturational, and physical readiness for sport
participation. Coaches and parents should be educated concerning common sport-
specific injuries and should promote at least one to two days of rest each week to allow
young athletes to recover. While sports diversification should be promoted before
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adolescence, parents should also be careful to limit the number of teams their child
participates on to allow for the suggested amount of rest. Young athletes’ training
should focus on skill acquisition and general fitness and should be progressively and
gradually increased, especially during growth spurts.
DISCUSSION
An association exists between youth sports specialization and increased risk of
injury10,11 and sport attrition.14,16 Age of specialization, hours spent in sport participation,
and organized sport structure appear to be highly associated factors for increased
injury,10 with specialized athletes typically being older, taller, and heavier than multisport
athletes.11 Studies14,16 reveal a negative relationship between specialization and current
sport participation, but also show perception of participation to be more influential than
specialization in sport enjoyment as adults. Reasons for specialization include fitness,
development of skills, and feelings of competence, while reasons for attrition include a
lack of time, interest, and fun.16 Most experts recommend delayed specialization,1,7,19,20
appropriate rest, nutrition, skill progression, and random practice to prevent the negative
effects associated with early specialization. Regardless of specialization or
diversification status, it is recommended that parents of young athletes should limit how
many total teams their child participates on in order to facilitate adequate rest periods;20
however, no specific number of teams has been identified in the literature.
Brylinsky21 stipulates that the act of specialization, whether early or delayed, is
not as important as the quality of skill instruction the young athlete receives. This duty
heavily depends on the coach to plan appropriate use of practice time, provide
demonstration, and facilitate feedback to allow the athlete to improve skills and know his
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or her limitations. Deliberate practice to reinforce content is beneficial, but so is the act
of deliberate play, the latter requiring more planning to incorporate into an instructional
setting. Such play benefits the athletes by promoting a greater sense of competence
and self-regulation. Participation in sport at a young age in general provides many
beneficial opportunities for the athlete to learn respect, self-discipline, hard work, good
sportsmanship, and courage and may help the athlete in other areas of life involving
schoolwork, community involvement, and relationships with family and friends.22 The
young athletes that do specialize should do so for personal enjoyment of the sport,23 and
the coaches and parents of these athletes should provide the instructional and
emotional support necessary for the better overall health of the athlete.21
In this day and age, most parents want the best for their child and wish them the
most success. Over time, parenting ideals evolved insofar as long as the child grew up
to be successful, the parents were successful in raising their child.24 For many, sports
seemed the best avenue for their child to gain success with the additional good
parenting bonus of supportive and sacrificial involvement as booster volunteers,
spectators, chauffeurs, and financial backers. With the privatization and
commercialization of youth sport to include travel, competitive, and club teams that play
in specialized venues that are run year-round instead of the traditional 3- or 4-month
high school season, it is very easy for parents to enroll their child at a young age in a
sport or two on multiple teams year-round.24 It is not unheard of either for parents to
redshirt, or hold back, their children in sports where size is important in attempt to foster
success, most notably at the prospect of college scholarships, professional sports
leagues, and even elite Olympian status.5
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Despite the many benefits young athletes receive from sport participation, limiting
the sports in which they participate through specialization may also limit the
development of crucial fundamental motor skills.25 These skills are developed early on
in life, and some individuals develop them earlier than others. The early-maturing
athletes tend to excel compared to the late-maturing and receive more focused skill
development in their sport, and more specifically their position, in which they are
playing. Because of this talent,22 they are encouraged to specialize. The late-maturing
athletes struggle to keep up and compete with the early-maturing and either drop out or
are cut from that sport; however, this provides the opportunity for the late-maturing to
become more versatile in their fundamental motor skills repertoire compared to the
early-maturing who are stuck in their specialty skills and position.25 This allows the late-
maturing athletes better opportunity for transfer of skills compared to the early-
maturing,22 who then face a proficiency barrier on the mountain of motor development
as their limited skills narrow the base of their mountain and thus restricts ability to
perform well outside of their sport.25
The effects specialization has on injury risk are difficult to study due to the
numerous variables involved, such as maturation rates, sport requirements, and training
techniques.23 Increased participation and exposure increased the risk for injury. As
results from studies9,10 demonstrated, overuse injuries commonly occur with sports
specialization. This is due to repetitive microtrauma in one sport, but overuse injury can
also occur in the multisport athlete who participates in two or more sports that
emphasize the same extremity or have inadequate rest between activities or seasons.3
While there are some sport-specific benefits to specialization,26 the effects of
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overtraining that are associated with specialization outweigh the benefits.23 Parents,
coaches, physicians, and athletes should be familiar with the warning signs and
symptoms of overuse injury and seek appropriate intervention to prevent worse injury
from occurring.3
Limitations
There are many variables associated with early sports specialization that make it
difficult to determine a precise cause and effect relationship. Much of the current
literature is expert/association recommendations based on theories or concepts of why
or why not sports specialization is beneficial or detrimental to the athlete’s health. More
empirical evidence is currently being gathered in order to describe the relationships and
effects early sports specialization has with and on the young athlete’s development,
health, and performance success. Because this evidence is still emerging, and therefore
unpublished, there is very little evidence from which to draw precise conclusions more
than mere association relationships.
Clinical Relevance
Athletic trainers often work with adolescent athletes who suffer from overuse
injuries associated with early specialization, intense training, and inadequate rest
periods. In order to reduce further risk of overuse injury and attrition from activity,
athletic trainers should educate athletes, parents, and coaches about the inherent risks
associated with early sports specialization and should encourage adequate rest from
sport activity. The early signs and symptoms of overuse injury recognizable by an
athletic trainer should serve as a warning to modify activity and should also be
conveyed to parents, coaches, and athletes as an important and easy way to determine
16
appropriate levels of sport involvement. The benefits of sport diversification in
conjunction with appropriate rest periods should also be shared with and embraced by
athletes, parents, and coaches.
CONCLUSIONS
Early sports specialization contributes to increased risk of overuse injuries in
young athletes and contributes to greater rates of attrition from activity in young
adulthood. Training and rest should be balanced to diminish incidence of fatigue, and
specialization should be delayed to decrease sport attrition. Focus should be placed on
the quality of skill instruction, and athletes should be allowed to experiment in different
sports and positions in order to develop a wide base of fundamental motor skills. The
young athlete needs appropriate emotional and instructional support from coaches and
parents in order to maximize a positive overall sport experience. More prospective
evidence is needed to clearly define the effects and relationships early sports
specialization has on youth and adolescent athletes’ health.
17
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Recreat Dance. 2010;81(8):19-21,28.
26.Mattson JM, Richards J. Early specialization in youth sport: A biomechanical
perspective. J Phys Educ Recreat Dance. 2010;81(8):26-28,39.
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FIGURE 1. Process of Study Selection
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Search of PubMed, MEDLINE, CINAHL, and Physical Therapy & Sports Medicine Collection
Search terms: “child and child development and youth sports specialization or sports
specialization” and “adolescent and adolescent developments and youth sports specialization or sports specialization.”
16 articles written in English discussing or examining the effects of early sports specialization on youth and adolescent athletes
4 original research articles and 4 expert/association recommendation articles included after reading abstracts
8 articles included in the final analysis:Jayanthi et al, 20131
AAP Committee on Sports Medicine and Fitness, 20007
Jayanthi et al, 201410
Hall et al, 201411
Russell WD, Limle AN, 201314
Russell WD, 201416
Johnson JH, 200819
DiFiori JP, 201020
FIGURE 2. AAP Committee on Sports Medicine and Fitness Recommendations7
1. Children are encouraged to participate in sports at a level consistent with their abilities and interests. Pushing children beyond this limits is discouraged as is specialization in a single sport before adolescence.
2. Pediatricians should work with parents to ensure that the child athlete is being coached by persons who are knowledgeable about proper techniques, equipment, and the unique physiological and emotional characteristics of young competitors.
3. In the absence of prospective markers of excessive physical stress, physicians and coaches should strive for early recognition and prevention and treatment of overuse injuries (tendinitis, apophysitis, stress fractures, “shin splints”). Child athletes should never be encouraged to “work through” such injuries. Treatment recommendations for overuse injuries that include only “rest” or cessation of the sport are unlikely to be followed by the committed child athlete and are unlikely to adequately address the risk of further injury.
4. The conditions of child athletes involved in intense training should be monitored regularly by a pediatrician. Attention should be focused on serial measurements of body composition, weight, and stature; cardiovascular findings; sexual maturation; and evidence of emotional stress. The pediatrician should be alert for signs and symptoms of overtraining, including decline in performance, weight loss, anorexia, and sleep disturbances.
5. The intensely trained, specialized child athlete needs ongoing assessment of nutritional intake, with particular attention to total calories, a balanced diet, and intake of iron and calcium. Serial measurements of body weight are particularly important in ensuring the adequacy of caloric intake and early identification of pathologic eating behaviors.
6. The child athlete, family, and coach should be educated by the pediatrician about the risks of heat injury and strategies for prevention.
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TABLE 1. Characteristics of Included Original Research Articles
Author(s) Subjects/Groups Methods Outcome Measures
Results
Jayanthi et al10
1,206 young athletes ages 7-18 yo (50.7% male) recruited from sports medicine and primary care clinics.
Injured athletes from sports medicine clinic; healthy controls from two primary care clinics
Baseline evaluation collecting injury data and assessing risk factors; longitudinal follow up data collection is ongoing.
Independent variables were hours per week of organized sport, gym, free play, sports specialization, and growth rate; dependent variables were total injuries, overuse injuries, serious overuse injuries, and acute injuries.
Injured athletes were older (14.1±2.1 yo) and spent more time in organized sport (11.3±6.9 hr) than uninjured athletes (12.9±2.6 yo; 9.4±8.2 hr; p<.001). After adjustments, specialization remained an independent risk factor for injury (OR 1.48, p<.05). Athletes who spent more hours per week in sport than their age (p<.05) and in >2 times more organized sports than free play (p=.001) were more likely to sustain serious overuse injury.
Hall et al11 546 female athletes (357 multisport; 189 single sport—66 basketball, 57 soccer, and 66 volleyball) with diagnoses of patellofemoral pain (PFP) recruited from 5 middle schools and 4 high schools in one county public school district in Kentucky.
Completion of standardized history and physician-administered physical examination for presence of PFP; Normalization of sports participation data by sport season, with each sport accounting as one season of exposure.
Incidence rate ratios (IRR) and 95% confidence intervals (CI).
Specialization increased the relative risk of PFP 1.5 times (95% CI: 1.0-2.2; p=.038). Specific diagnoses of Sindig-Larsen-Johansson/patellar tendionopathy and Osgood-Schlatter Disease increased 4-fold in specialized athletes than in multisport athletes.
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TABLE 1. Characteristics of Included Original Research Articles (continued)
Russell and Limle14
153 participants ages 18-22 yo in general education wellness courses at a mid-size Midwestern university (71 male, 82 female).
87 self-reported specialized athletes (56.9%); 66 self-reported multisport athletes
Survey; included questions related to sports specialization and past and present sports participation, a 17-item examination of general retrospective perceptions of youth sport, and the Physical Activity Enjoyment Scale, (PACES).15
Descriptive statistics, independent t-tests, chi-square procedures, and multiple regression analyses.
The most frequent specialized sports reported were basketball and soccer. 32 of the 87 specialized participants reported specializing at or before age 8. Of all 153 participants, 53 (35.3%) reported attrition. Independent t-tests were nonsignificant for specialization’s effect on activity enjoyment, current aerobic exercise, current strength training, and overall retrospective perceptions of youth sport participation (p>.05). Chi square testing revealed a significant negative relationship between specialization and current sport participation (χ2(2)=8.77, p<.05).
Russell16 200 participants ages 17-22 yo in general education wellness courses at a mid-size Midwestern university (93 male, 107 female).
113 self-reported specialized athletes (56%); 87 self-reported multisport athletes
Survey; included questions related to sports specialization and past and present sports participation, a 9-item examination of reasons for youth sports participation and withdrawal, the PACES,15 and the Sport Motivation Scale (SMS).17
Descriptive statistics, independent t-tests, chi-square procedures, and one-way MANOVAs.
In the specialized group, 101 (89%) specialized before adolescence, 72 (71%) before age 10, and 21% before age 6. 103 of 200 participants (51.5%) reported attrition from sport as young adults. Specializers’ reasons for attrition were lack of time (n=17), lost interest (n=12), and lack of fun (n=10); nonspecializers’ reasons were lost interest (n=10) and lack of time (n=8).
Chi-square testing found participants who specialized were less likely to participate in sport as a young adult (χ2(2)=6.43, p<.05).
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TABLE 2. Characteristics of Included Expert/Association Recommendations
Author(s) Expert/Association Recommendations
Jayanthi et al1 Specialization should be delayed until late adolescence to optimize sports success and reduce injury risk.
AAP Committee on Sports Medicine and Fitness7
Sports participation should be at the child’s desire and specialization delayed until adolescence. The child’s health should be monitored for developmental growth and abnormalities. Physicians, coaches, and parents should recognize the signs and symptoms of overuse injury.
Johnson19 Youth sports should involve gradual skill progression, random practice, rest, and age-appropriate activities. Change of activity should occur every 2-3 months and diversification embraced.
DiFiori20 Regardless of specialization or diversification, the amount of time spent in sport and the number of teams a child belongs to should be limited. Training should focus on skill acquisition, general fitness, and should follow a progression.
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