1. A STUDY OF THE EFFECTS OF YOUTH COMPETITVE SPORTS ON
REPETITIVE MOTION INURIES DURING PUBERTY
by
Richard L. Brenkmann
A master’s project submitted in partial fulfillment of the requirements for the degree
of
Master of Education
in
Health, Physical Education, and Recreation
Approved:
Dr. John M. Kras,Chair Date
Dr. Richard Gordin, Member Date
Dr. Dennis Nelson, Member Date
Dr. Dennis Dolny, Department Head Date
UTAH STATE UNIVERSITY
Logan, Utah
2011

2. A STUDY OF THE EFFECTS OF YOUTH COMPETITVE SPORTS ON
REPETITIVE MOTION INURIES DURING PUBERTY
Problem Statement
When I was young, my friends and I played whatever sport was in season,except for the
summer when the sport relied on available shade. We never focused on any one particular sport
all the way through high school. Today’s youth are starting to focus on one sport at a much
earlier age in an attempt to elevate their abilities to a level of hopefully being able to become
professional athletes some day. Some kids are starting to specialize in competitive leagues as
early as eight years old, and really only playing that sport until they get out of high school. This
practice, I believe, is dangerous for the young person who does this. Many of these competitive
players end up with nagging injuries that plague them throughout their career.
Most of these injuries are from repetitive motions that put an unnatural strain on a
particular set of joints and muscles. These injuries are mere nuisances in the beginning, but
without proper rest and care the injuries will become chronic and more problematic as the child
gets older. These injuries are developing new names based on the sport such as soccer knee and
pitcher’s elbow. An individual who focuses on one sport also misses out on the skills that cross
over from one sport to the next, and can make a player an overall better player. By participating
in other sports, the joints and muscles will strengthen which could also prevent other injuries.
The literature suggests that youth who participate in only one sport, without decent rest,and
without experiencing “muscle confusion” (Bosgieter, 2010) can suffer overuse injuries that can
eventually develop into chronic injuries. The problem I will study is how prevalent are these
injuries in one sport participants between the ages of ten to 16 years old.

3. 2
Purpose and Objectives
The purpose of this paper is to show a correlation between the repetitive injuries and the
playing of only one sport during the developmental years through puberty. The objectives would
be to show to researchers and parents the need to participate in multiple activities to increase the
skills in the main sport. I would also hope to encourage parents and youth to consider playing
multiple sports because I do not know too many eight year olds who are already planning a career
in something specific. Burnout among these athletes is high because they have nothing else going
on but this one sport, and eventually they may grow to despise the sport. There are several
groups that have banded together to create “’the STOP Sports Injuries’ campaign to raise
awareness about this trend and help prevent athletic overuse and trauma injuries in children”
(Initiative to Stop, 2010). I would hope conscientious readers would realize that this is true and
encourage play for plays sake in their children.
ReviewofLiterature
Competitive sports programs have been growing over the last severalyears with not only
local leagues, but regional and national leagues as well. There are competitive leagues in
basketball, baseball, soccer,hockey and rugby that have contests throughout the year. Most
competitive teams also play in tournaments on weekends all over the region in which they live, as
well as league games during the week. There are those who argue that the “all-embracing goal
for children's sport programs: helping young athletes emerge from the sport experience as
responsible, autonomous people” (Stiehl, 1990, p 207). “Coaches should include this goal in their
personal coaching philosophy and many have not done so” (Stiehl, 1990, p 207). This
responsibility should fall to “all adults, whether coaching or not, can help young athletes learn to
become responsible for themselves” (Stiehl, 1990, p 207). “Sports programs for young people

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have grown so rapidly that scholars and practitioners alike are hard pressed to keep up with new
knowledge” (Stiehl, 1990, p 205). It is not just the psychological toll, but also the physical toll
that youth face,especially in the repetitive actions that occur in competitive sports.
The adults who participate in competitive youth sports are the parents. The influence of
parents on the youth players is important in determining the efforts of the child, as well as the
level of soreness that the child will endure. “The degree of involvement a parent makes in their
child's sport makes a statement about the relative importance of this domain” (Barber,1999). If a
child senses that playing and doing well is important to the parent, then the child “will adopt
values and beliefs similar to their parents” (Barber,1999). Parents range in the level of
involvement from being over-involved to under-involved. Barber (1999) looked at the
relationship of parents to their children in youth sports, and found that youth participated for fun,
but initially for many it may have been encouragement from their parents to participate.
With the move to earlier specialization, it should be understood that “The American
Academy of Pediatrics (AAP) Committee on Sports Medicine and Fitness does not recommend
specialization before the age of 12 or 13 years” (Rosenbaum,p 255). The early start of sports
specialization can lead to injury due to micro-trauma to the growth plate. “Often, younger
athletes do not recognize overuse symptoms until they become debilitating” (Rosenbaum, p 256).
Rosenbaum also stated that “adolescents are not as coordinated or may not yet have adjusted to
physiological changes during an increased velocity of growth. This could result in altered
flexibility with inherent muscle imbalances, making them vulnerable to injury” (p 256). The
AAP recommends as an alternate to early sport specialization is sports diversification, which
would be considered as sampling (multiple sport experiences) from 6 to 12, and specialization
coming after in ages 13 to 15 (Rosenbaum, p 256).

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There have been a number of studies that have looked at various injuries in youth sports
and the causes behind them. Much of the literature focuses on the kinds of injuries associated
with contact or traumatic stress injury. The focus of my project is to look at repetitive use
injuries due to overuse and not enough rest between competitive activities. “Orthopedic surgeons
are also seeing a rise in the number of youth sports injuries in general, and in the number of
younger athletes who suffer overuse injuries” (Initiative to Stop, 2010). The literature that
focuses on the repetitive injuries seems to be mostly involving the sports of soccer and lower
extremity issues, and baseball pitchers with injuries involving the shoulder and elbow.
A New York Times Magazine article discusses the prevalence of elbow and shoulder
injuries in youth baseball. Berler (2009) did a study of the increasing number of youth players
who were having elbow and shoulder surgeries at much younger ages. “A 13 year old might
pitch Sunday for his travel team, Monday for his middle school team, and Wednesday for his
Babe Ruth team” (Berler, 2009). There are some players today who are “playing baseball nearly
year round, to the exclusion of all other sports” (Berler, 2009). “Parents failed to realize to
recognize that kids need 3 – 4 months of recovery time each year” (Berler,2009).
Childress (2003) describes pitching as “one of the most dynamic motions in sport. This
is demonstrated when the average time from initial foot contact of the stride leg to ball release is
0.145 seconds” (p 1). Injuries to the elbow and shoulder are the normal injury site for youth
baseball players, with the most common being Little League Elbow. “The stress placed on the
elbow during pitching has been implicated as the cause of little league elbow” (Childress, 2003, p
2). Adolescent elbow injuries are repetitive injuries that are mostly skeletal in nature, and rarely
involve the muscle tendon that happens with adults. “When the elbow of an adolescent is

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subjected to repeated stress,the growth plates are more vulnerable to injury” (Childress 2003, p
3)
Other studies have shown that there is a deficiency in training and proper technique that
is the problem causing the shoulder and elbow pain. Aguinaldo, Butters and Chambers (2007)
looked at a concern described as “’throwing with too much arm,’ in which the energy from trunk
rotation is transferred to the upper arm too early and dissipated instead of being applied to the
hand and ball. (p 43) Aguinaldo, et al studied “the biomechanical patterns of trunk rotation and
shoulder joint torque during baseball pitching between professional, collegiate, high school, and
youth players.” (p 44) Although including some items from an older class, this information is
pertinent to this study because it helps to establish a background of the mechanics that make for
safer pitching. “The current study demonstrated that pitchers who rotated their torsos later in their
delivery exhibited less shoulder internal rotation torque (Aguinaldo, et al, 2007, p 48). Based on
their work, Aguinaldo, et al surmised “that the sequence of body segmental motion was
compromised when the trunk rotated too early, because part of the rotational energy was lost and
made up for by the upper extremity” (2007 p 48).
In a broader study of reported arm pain, Lyman, Fleisig, Waterbor,Funkhouser, Pulley,
Andrews,Osinski, and Rosman looked at 298 youth baseball pitchers over two seasons. The
study was designed “to evaluate the frequency of elbow and shoulder complaints in young
pitchers and to identify the associations between pitch types, pitch volume, and other risk factors
for these conditions.” (Lyman et al, 2001, p 1803) Each participant was contacted after a pitching
outing and asked a series of questions that would help the researchers “identify arm complaints.
Generalized estimating equations were used to assess associations between arm complaints and
independent variables. Results: The frequency of elbow pain was 26%; that of shoulder pain, 32%
” (Lyman, et al, 2001, 1803). Lyman, et al (2001) identified severalrisk factors that seemed to be

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an underlying variable in both locations which included “playing baseball outside the league,
decreased self-satisfaction, arm fatigue during the game pitched, and throwing fewer than 300 or
more than 600 pitches during the season” (1803). It was also noticed that throwing more than 75
pitches in a game will also lead to shoulder or elbow pain. Lyman, et al (2011) concluded that
“arm complaints are common, with nearly half of the subjects reporting pain. The factors
associated with elbow and shoulder pain were different, suggesting differing etiologies.
Developmental factors may be important in both, to lower the risk of pain at both locations young
pitchers probably should not throw more than 75 pitches in a game” (1083).
In a different study by Fleisig, Weber, Hassell and Andrews (2009), they found that “the
risk of Adolescents who competitively pitch more than 85 pitches per game, more than 8 months
out of a year or with arm fatigue are severaltimes more likely to require elbow surgery. Poor
pitching mechanics also appear to contribute to injury risk” (p254). Fleisig, et al. (2009) pointed
to “the number of pitches thrown has the strongest correlation to youth pitching injuries” (p 250).
Although Little League Baseball has created guidelines limiting pitch counts, “many independent
and travel teams have no rules restricting pitch counts, inning limits, or days of rest” (Fleisig, et
al. 2009, p 251). A player who may be a good pitcher could end up pitching 3 or 4 days a week,
throwing hundreds of pitches during that time. Major League baseball pitchers are monitored
constantly, and rarely throw more than 115 pitches in a week, and some coaches are asking youth
to throw more with less rest. Fleisig, et al. (2009) stated that: “Our impression is that in past
generations, most children engaged in a reasonable amount of sports participation; now, there are
many children who do not play enough sports, and a smaller ‘elite’ group of children who
participate too much in one particular sport” (p 252).
Ray (2010) took a more medical look at the injuries incurred by youth and found “that
taller and heavier children have an increased risk of injury to the elbow and shoulder than their

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counterparts of the same age. One possible explanation for this finding may include their higher
level of performance and subsequent overuse by coaches set on winning” (p 295). It seems that
many youth pitching injuries are blamed on the throwing of a curveball. Ray (2010) states
“shoulder internal rotation torque and proximal force as well as elbow varus torque and proximal
force were significantly less for the curveball than the fastball when comparing the biomechanics
of youth pitchers throwing the fastball, curveball, and change up. Although more research in this
important area is needed, this suggests that the curveball might not be more harmful to the youth
pitcher than the fastball” (p 295-296). More simply put, the torque from a properly thrown
curveball is less on the elbow and shoulder, and likely less harmful (although the emphasis should
be put on a properly thrown curveball) than a fastball or change-up.
Kocher, Waters,and Micheli (2000) also approached Little League Elbow from a more
mechanical standpoint, looking at the biomechanics of the injury. “Recognition of injury patterns
with early activity modification and the initiation of efficacious treatment can prevent
deformity/disability and return the youth athlete to sport” (Kocher,et al. 2000, p 118). Pitchers
suffer from “injury to the paediatric (sic) shoulder from throwing is a result of microtrauma (sic)
from repetitive motions of large rotational forces” (Kocher,et al. 2000, p 119).
Ogden and Warneke (2010) took a look at the correlation between college baseball
pitchers and youth competitive baseball pitchers as to whether these players had more need for
surgery later, and also had more pain from pitching. Select, or competitive, teams are starting
play earlier, as early as 7 or 8 years old, and these kids are encouraged to play year-round. As
stated earlier, it is recommended by researchers and doctors that players take up to 4 months off
of a particular sport in a year to rest and recover. Ogden and Warneke (2010) state “that the
youths who grow to be the best adult athletes are often those who engage in a variety of sports, or
multilateral development, in their earliest years. During those years children should be building
the basic skills of running, jumping, and throwing.” Although these select teams do seem to

9. 8
show a correlation to transitioning to the higher leagues, players were stricken with more stress
and burnout, and sometimes outright quit before reaching that level. Those who participated at
higher skill positions like pitcher and catcher also showed more signs of overuse injuries as they
progressed from level to level.
Studies have also looked at the incidence of injuries in youth soccer players. Just like the
use of the term Little League Elbow, soccer has its own malady of overuse called Soccer Knee.
This injury is characterized by the painful swelling of the patellar tendon, and is cause in large
part by the contraction of the quadriceps muscles to kick the ball and also to plant with the
opposite foot. This injury is less common in the recreational player who plays one game a week,
and practices once per week. Soccer Knee injuries are typically found in competitive soccer
players who will play and practice three or more times per week,and they often play 12 months
of the year. Another issue looked at by Viscovi and Van Heest (2009) was the number of ACL
injuries being suffered by female soccer players (p 394). The injuries in question are non contact
injuries that come from weak muscles that provide support to the knee joint. Viscovi and Van
Heest (2009) investigated the effectiveness of “the Prevent Injury Enhance Program” on
adolescent female soccer players (p 394). “Epidemiological studies with soccer players indicate
that the most common anatomical site for injury is the lower extremities. Of particular concern
for female soccer players is that following puberty they are three times more likely to suffer an
anterior cruciate ligament (ACL) injury compared with the male soccer players” (Viscovi and
Van Heest,2009, p 394). Although this study was designed to look at injury prevention training,
it showed that part of this rash of ACL injuries could have as much to do with overuse. The
testing was conducted on four club soccer teams who were playing during a summer outdoor
season,with two teams running the training program and two who were doing an ordinary warm
up. At issue were the difference between warm up regimens and whether they decreased injury
or improved performance. There seemed to be no difference in the effects of the two warm-ups,

10. 9
and yet they were working with club athletes who played year round. The look at what was
happening in the injury situation could have been about rest time, time off, and healing of the
micro tears of the ligaments, tendons and muscles that occur when the adolescent soccer player
plays and practices 4 or more times per week. The study concluded “, these programs were
designed with an aim of reducing the risk of non-contact ACL injuries, not enhancing
performance. However,if we are to convince coaches to implement an injury prevention
program, then investigators and clinicians should continue to modify program variables and
develop regimens that have promise to deliver dual benefits – improved performance and reduced
injury risk” (Viscovi and Van Heest,2009, p 401).
In a 10 year study of common injuries in elite youth French soccer players, Le Gall,
Carling, Reilly, Vandewalle, Church, and Rochcongar (2006) found that “players younger than 14
years incurred more injuries in training and sustained more growth-related overuse disorders.
Older players were more often injured during matches. Injury incidence and the frequency of
overuse disorders were highest early in the season” (p 928). The study seemed to suggest the
younger “players still lacked injury-avoidance skills or could have been undertaking too much
intensive training at this age” (Le Gall et al., 2006, p 934). Le Gall et al. (2006) further stated
that “injuries in less experienced, younger players may be owing to weaknesses in technical and
tactical ability as well as in muscle strength, endurance,and coordination” (p 934). “There was a
significantly greater amount of osteochondral disorders at the apophyseal or epiphyseal growth
areas of bones, which are linked to overuse, in U14 players, suggesting that this is a high-risk
group” (Le Gall et al., 2006, p 936).
Elias (2001) conducted a 10 year study that differed from Le Gall et al. by focusing his
study on injuries incurred during a major soccer tournament only. Elias chose the USA Cup

11. 10
Soccer Tournament held in Minnesota every July to study the injuries that were occurring during
the competition at all levels. This tournament lasts 6 days and has “over 800 teams from 23
countries participating in age groups under-12 to under-19. All games are played at the National
Sports Center/Blaine Soccer Complex, which has 55 fields on one site” (Elias, 2001, p 359). At
the end of the ten year study, Elias (2001) holds the notion that “although females are injured at a
rate slightly greater than males, there is a trend suggesting that the overall difference is becoming
less significant” (p 367). This was related to the aggressiveness of play between the sexes,as
well as the differences experienced in conditioning.
Gomez, Neufeld, and Cosby (1996) chose to determine whether middle school soccer
players could “assess the probability of success with which … players could correctly localize
lower leg pain to sites of common overuse injuries” (p 335). The goal is to develop an instrument
that will help youth understand and care for overuse injuries that can lead to significant injuries
later if not cared for early enough. “The majority of overuse injuries in young athletes occur in
the lower extremity. The common overuse injuries of the leg in youngsters include shin splints,
patellar tendonitis, plantar fasciitis, Osgood-Schlatter disease,and Sever disease” (Gomez, et al.,
1996, p 335). Gomez, et al. (1996) discovered that these nagging injuries were rarely significant
enough to warrant a trip to a doctor or trainer (p 338). “Since athletes with overuse injuries can
often ‘play through’ the pain, it may be more useful in evaluating the clinical significance of
these injuries to ask about the extent to which the pain compromised the athletes’ performance”
(Gomez et al. 1996, p 338).
With the recent emphasis being placed on head injuries, and the cumulative effects on the
brain of repeated minor concussions, a new field has grown out of competitive injuries involving
the heading of the ball. Contact among soccer players is generally not significant enough to

12. 11
warrant more than a look at contusions, but heading a soccer ball repeatedly can lead to minor
concussive events in the brain. Salinas, Webbe, and Devore (2009) looked at this phenomenon
and found that “the head injury rate accounts for 4.9–22% of soccer injuries in adolescents” (p
15). “The majority of soccer headings were direct rather than flicks. Almost half of our
participants reported headache and one-fourth reported dizziness after instances of heading the
ball” (Salinas, et al., 2009, p 15). “Children are even more likely to lack awareness of concussion
symptoms and so may not accurately report their symptoms. Without knowledge of such critical
information about their child’s symptoms, parents may not understand that these injuries require
medical attention” (Salinas, et al., 2009, p 16). Parents,coaches and players need to understand
both the symptoms and related problems that can come from repeated concussions. “In soccer
play, concussive head injuries are most likely to happen when two players make a mutual attempt
to head the ball. Heads banging together or elbows and fists striking a head are common. Less
common are injuries related to the ball striking the head” (Salinas, et al., 2009, p 17).
Discussion
As this information is looked at, I understand that repetitive injury is not limited to only
the competitive sports, but can occur in recreational sports as well. In a humorous article for
Sports Illustrated,Rick Reilly looks at what could be considered the absurd side of competitive
sports, but there still is the need to look at the potential for injury when a child who is still
growing plays one sport exclusively.
“But then my wife gets to talking to some other moms at Justin's slap shot workshop, and
they say we're crazy if we don't have a 'performance-enhancement specialist' for our kids.
So she signs them both up with one. Then she finds out most of these girls have
'recruiting consultants' who make highlight reels of kids and send them to college

13. 12
coaches. I'm like, 'She's 14!' And my wife is like, 'You're gonna tell our little girl no?'
Then we add a rating-service guy and a sports psychologist and a webmaster” (Reilly,
2006, p 76).
Competitive sports are leading to new needs in pediatric health as nagging injuries become more
serious in nature. “Because it's unrealistic to expect an enthusiastic young athlete or an
overzealous parent to recognize the severity of the issue and consequently know when to ease
back, it's up to recreation professionals and youth sports administrators to get the word out on
preventing overuse injuries” (Bach and Shilling, 2008, p 24). Bach and Shilling (2008) went on
to further state:
“Today's youth athletics are rife with single- sport specialization, heavy practice
schedules, and year-round training. The result is that a disturbing number of young
athletes have their seasons chopped short—and their long-term health jeopardized—by
overuse injuries.
As more and more youngsters are forced to visit doctors' offices for everything
from bone fractures and Little League elbow to shin splints and damaged knees,the
alarm is being sounded loud and clear by sports medicine professionals that too much of
the same activity can do more harm than good. Overuse injuries are sabotaging what
should be a fun and rewarding experience for millions of young athletes. These children,
who are breaking down due to the constant stress being placed on their young and
developing bodies, often face the unenviable prospect of long and sometimes painful
rehabilitations — and even surgery—to repair the damage” (p 24).
Conclusion
The youth are playing one sport exclusively more and more, and many are starting at a
much earlier age. The literature shows that, at least while growth is continuing to occur, there

14. 13
should be multiple sports tried by youth so that the muscles and bones can rest and recover.
Playing one sport year round never allows for the micro trauma to heal. I look at Washington
Nationals pitching phenom Stefan Strassbourg, and I see a young man who probably focused on
baseball at an early age. Granted,he signed a big money contract, but since being called up to the
majors at 19, he has spent more time recovering from elbow and shoulder pain than he has
playing. The micro trauma and lack of healing has caught up with him, and a bright future in
baseball is looking rather tenuous at this time.

15. 14
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